/*** 2001 September 15**** The author disclaims copyright to this source code. In place of** a legal notice, here is a blessing:**** May you do good and not evil.** May you find forgiveness for yourself and forgive others.** May you share freely, never taking more than you give.***************************************************************************** This header file defines the interface that the SQLite library** presents to client programs. If a C-function, structure, datatype,** or constant definition does not appear in this file, then it is** not a published API of SQLite, is subject to change without** notice, and should not be referenced by programs that use SQLite.**** Some of the definitions that are in this file are marked as** "experimental". Experimental interfaces are normally new** features recently added to SQLite. We do not anticipate changes** to experimental interfaces but reserve the right to make minor changes** if experience from use "in the wild" suggest such changes are prudent.**** The official C-language API documentation for SQLite is derived** from comments in this file. This file is the authoritative source** on how SQLite interfaces are supposed to operate.**** The name of this file under configuration management is "sqlite.h.in".** The makefile makes some minor changes to this file (such as inserting** the version number) and changes its name to "sqlite3.h" as** part of the build process.*/#ifndef SQLITE3_H#define SQLITE3_H#include<stdarg.h> /* Needed for the definition of va_list *//*** Make sure we can call this stuff from C++.*/#ifdef __cplusplusextern"C"{#endif/*** Provide the ability to override linkage features of the interface.*/#ifndef SQLITE_EXTERN# define SQLITE_EXTERN extern#endif#ifndef SQLITE_API# define SQLITE_API#endif#ifndef SQLITE_CDECL# define SQLITE_CDECL#endif#ifndef SQLITE_APICALL# define SQLITE_APICALL#endif#ifndef SQLITE_STDCALL# define SQLITE_STDCALL SQLITE_APICALL#endif#ifndef SQLITE_CALLBACK# define SQLITE_CALLBACK#endif#ifndef SQLITE_SYSAPI# define SQLITE_SYSAPI#endif/*** These no-op macros are used in front of interfaces to mark those** interfaces as either deprecated or experimental. New applications** should not use deprecated interfaces - they are supported for backwards** compatibility only. Application writers should be aware that** experimental interfaces are subject to change in point releases.**** These macros used to resolve to various kinds of compiler magic that** would generate warning messages when they were used. But that** compiler magic ended up generating such a flurry of bug reports** that we have taken it all out and gone back to using simple** noop macros.*/#define SQLITE_DEPRECATED#define SQLITE_EXPERIMENTAL/*** Ensure these symbols were not defined by some previous header file.*/#ifdef SQLITE_VERSION# undef SQLITE_VERSION#endif#ifdef SQLITE_VERSION_NUMBER# undef SQLITE_VERSION_NUMBER#endif/*** CAPI3REF: Compile-Time Library Version Numbers**** ^(The [SQLITE_VERSION] C preprocessor macro in the sqlite3.h header** evaluates to a string literal that is the SQLite version in the** format "X.Y.Z" where X is the major version number (always 3 for** SQLite3) and Y is the minor version number and Z is the release number.)^** ^(The [SQLITE_VERSION_NUMBER] C preprocessor macro resolves to an integer** with the value (X*1000000 + Y*1000 + Z) where X, Y, and Z are the same** numbers used in [SQLITE_VERSION].)^** The SQLITE_VERSION_NUMBER for any given release of SQLite will also** be larger than the release from which it is derived. Either Y will** be held constant and Z will be incremented or else Y will be incremented** and Z will be reset to zero.**** Since [version 3.6.18] ([dateof:3.6.18]), ** SQLite source code has been stored in the** <a href="http://www.fossil-scm.org/">Fossil configuration management** system</a>. ^The SQLITE_SOURCE_ID macro evaluates to** a string which identifies a particular check-in of SQLite** within its configuration management system. ^The SQLITE_SOURCE_ID** string contains the date and time of the check-in (UTC) and an SHA1** hash of the entire source tree.**** See also: [sqlite3_libversion()],** [sqlite3_libversion_number()], [sqlite3_sourceid()],** [sqlite_version()] and [sqlite_source_id()].*/#define SQLITE_VERSION "3.15.1"#define SQLITE_VERSION_NUMBER 3015001#define SQLITE_SOURCE_ID "2016-11-04 12:08:49 1136863c76576110e710dd5d69ab6bf347c65e36"/*** CAPI3REF: Run-Time Library Version Numbers** KEYWORDS: sqlite3_version, sqlite3_sourceid**** These interfaces provide the same information as the [SQLITE_VERSION],** [SQLITE_VERSION_NUMBER], and [SQLITE_SOURCE_ID] C preprocessor macros** but are associated with the library instead of the header file. ^(Cautious** programmers might include assert() statements in their application to** verify that values returned by these interfaces match the macros in** the header, and thus ensure that the application is** compiled with matching library and header files.**** <blockquote><pre>** assert( sqlite3_libversion_number()==SQLITE_VERSION_NUMBER );** assert( strcmp(sqlite3_sourceid(),SQLITE_SOURCE_ID)==0 );** assert( strcmp(sqlite3_libversion(),SQLITE_VERSION)==0 );** </pre></blockquote>)^**** ^The sqlite3_version[] string constant contains the text of [SQLITE_VERSION]** macro. ^The sqlite3_libversion() function returns a pointer to the** to the sqlite3_version[] string constant. The sqlite3_libversion()** function is provided for use in DLLs since DLL users usually do not have** direct access to string constants within the DLL. ^The** sqlite3_libversion_number() function returns an integer equal to** [SQLITE_VERSION_NUMBER]. ^The sqlite3_sourceid() function returns ** a pointer to a string constant whose value is the same as the ** [SQLITE_SOURCE_ID] C preprocessor macro.**** See also: [sqlite_version()] and [sqlite_source_id()].*/SQLITE_APISQLITE_EXTERNconstcharsqlite3_version[];SQLITE_APIconstchar*sqlite3_libversion(void);SQLITE_APIconstchar*sqlite3_sourceid(void);SQLITE_APIintsqlite3_libversion_number(void);/*** CAPI3REF: Run-Time Library Compilation Options Diagnostics**** ^The sqlite3_compileoption_used() function returns 0 or 1 ** indicating whether the specified option was defined at ** compile time. ^The SQLITE_ prefix may be omitted from the ** option name passed to sqlite3_compileoption_used(). **** ^The sqlite3_compileoption_get() function allows iterating** over the list of options that were defined at compile time by** returning the N-th compile time option string. ^If N is out of range,** sqlite3_compileoption_get() returns a NULL pointer. ^The SQLITE_ ** prefix is omitted from any strings returned by ** sqlite3_compileoption_get().**** ^Support for the diagnostic functions sqlite3_compileoption_used()** and sqlite3_compileoption_get() may be omitted by specifying the ** [SQLITE_OMIT_COMPILEOPTION_DIAGS] option at compile time.**** See also: SQL functions [sqlite_compileoption_used()] and** [sqlite_compileoption_get()] and the [compile_options pragma].*/#ifndef SQLITE_OMIT_COMPILEOPTION_DIAGSSQLITE_APIintsqlite3_compileoption_used(constchar*zOptName);SQLITE_APIconstchar*sqlite3_compileoption_get(intN);#endif/*** CAPI3REF: Test To See If The Library Is Threadsafe**** ^The sqlite3_threadsafe() function returns zero if and only if** SQLite was compiled with mutexing code omitted due to the** [SQLITE_THREADSAFE] compile-time option being set to 0.**** SQLite can be compiled with or without mutexes. When** the [SQLITE_THREADSAFE] C preprocessor macro is 1 or 2, mutexes** are enabled and SQLite is threadsafe. When the** [SQLITE_THREADSAFE] macro is 0, ** the mutexes are omitted. Without the mutexes, it is not safe** to use SQLite concurrently from more than one thread.**** Enabling mutexes incurs a measurable performance penalty.** So if speed is of utmost importance, it makes sense to disable** the mutexes. But for maximum safety, mutexes should be enabled.** ^The default behavior is for mutexes to be enabled.**** This interface can be used by an application to make sure that the** version of SQLite that it is linking against was compiled with** the desired setting of the [SQLITE_THREADSAFE] macro.**** This interface only reports on the compile-time mutex setting** of the [SQLITE_THREADSAFE] flag. If SQLite is compiled with** SQLITE_THREADSAFE=1 or =2 then mutexes are enabled by default but** can be fully or partially disabled using a call to [sqlite3_config()]** with the verbs [SQLITE_CONFIG_SINGLETHREAD], [SQLITE_CONFIG_MULTITHREAD],** or [SQLITE_CONFIG_SERIALIZED]. ^(The return value of the** sqlite3_threadsafe() function shows only the compile-time setting of** thread safety, not any run-time changes to that setting made by** sqlite3_config(). In other words, the return value from sqlite3_threadsafe()** is unchanged by calls to sqlite3_config().)^**** See the [threading mode] documentation for additional information.*/SQLITE_APIintsqlite3_threadsafe(void);/*** CAPI3REF: Database Connection Handle** KEYWORDS: {database connection} {database connections}**** Each open SQLite database is represented by a pointer to an instance of** the opaque structure named "sqlite3". It is useful to think of an sqlite3** pointer as an object. The [sqlite3_open()], [sqlite3_open16()], and** [sqlite3_open_v2()] interfaces are its constructors, and [sqlite3_close()]** and [sqlite3_close_v2()] are its destructors. There are many other** interfaces (such as** [sqlite3_prepare_v2()], [sqlite3_create_function()], and** [sqlite3_busy_timeout()] to name but three) that are methods on an** sqlite3 object.*/typedefstructsqlite3sqlite3;/*** CAPI3REF: 64-Bit Integer Types** KEYWORDS: sqlite_int64 sqlite_uint64**** Because there is no cross-platform way to specify 64-bit integer types** SQLite includes typedefs for 64-bit signed and unsigned integers.**** The sqlite3_int64 and sqlite3_uint64 are the preferred type definitions.** The sqlite_int64 and sqlite_uint64 types are supported for backwards** compatibility only.**** ^The sqlite3_int64 and sqlite_int64 types can store integer values** between -9223372036854775808 and +9223372036854775807 inclusive. ^The** sqlite3_uint64 and sqlite_uint64 types can store integer values ** between 0 and +18446744073709551615 inclusive.*/#ifdef SQLITE_INT64_TYPEtypedefSQLITE_INT64_TYPEsqlite_int64;typedefunsignedSQLITE_INT64_TYPEsqlite_uint64;#elif defined(_MSC_VER) || defined(__BORLANDC__)typedef__int64sqlite_int64;typedefunsigned__int64sqlite_uint64;#elsetypedeflonglongintsqlite_int64;typedefunsignedlonglongintsqlite_uint64;#endiftypedefsqlite_int64sqlite3_int64;typedefsqlite_uint64sqlite3_uint64;/*** If compiling for a processor that lacks floating point support,** substitute integer for floating-point.*/#ifdef SQLITE_OMIT_FLOATING_POINT# define double sqlite3_int64#endif/*** CAPI3REF: Closing A Database Connection** DESTRUCTOR: sqlite3**** ^The sqlite3_close() and sqlite3_close_v2() routines are destructors** for the [sqlite3] object.** ^Calls to sqlite3_close() and sqlite3_close_v2() return [SQLITE_OK] if** the [sqlite3] object is successfully destroyed and all associated** resources are deallocated.**** ^If the database connection is associated with unfinalized prepared** statements or unfinished sqlite3_backup objects then sqlite3_close()** will leave the database connection open and return [SQLITE_BUSY].** ^If sqlite3_close_v2() is called with unfinalized prepared statements** and/or unfinished sqlite3_backups, then the database connection becomes** an unusable "zombie" which will automatically be deallocated when the** last prepared statement is finalized or the last sqlite3_backup is** finished. The sqlite3_close_v2() interface is intended for use with** host languages that are garbage collected, and where the order in which** destructors are called is arbitrary.**** Applications should [sqlite3_finalize | finalize] all [prepared statements],** [sqlite3_blob_close | close] all [BLOB handles], and ** [sqlite3_backup_finish | finish] all [sqlite3_backup] objects associated** with the [sqlite3] object prior to attempting to close the object. ^If** sqlite3_close_v2() is called on a [database connection] that still has** outstanding [prepared statements], [BLOB handles], and/or** [sqlite3_backup] objects then it returns [SQLITE_OK] and the deallocation** of resources is deferred until all [prepared statements], [BLOB handles],** and [sqlite3_backup] objects are also destroyed.**** ^If an [sqlite3] object is destroyed while a transaction is open,** the transaction is automatically rolled back.**** The C parameter to [sqlite3_close(C)] and [sqlite3_close_v2(C)]** must be either a NULL** pointer or an [sqlite3] object pointer obtained** from [sqlite3_open()], [sqlite3_open16()], or** [sqlite3_open_v2()], and not previously closed.** ^Calling sqlite3_close() or sqlite3_close_v2() with a NULL pointer** argument is a harmless no-op.*/SQLITE_APIintsqlite3_close(sqlite3*);SQLITE_APIintsqlite3_close_v2(sqlite3*);/*** The type for a callback function.** This is legacy and deprecated. It is included for historical** compatibility and is not documented.*/typedefint(*sqlite3_callback)(void*,int,char**,char**);/*** CAPI3REF: One-Step Query Execution Interface** METHOD: sqlite3**** The sqlite3_exec() interface is a convenience wrapper around** [sqlite3_prepare_v2()], [sqlite3_step()], and [sqlite3_finalize()],** that allows an application to run multiple statements of SQL** without having to use a lot of C code. **** ^The sqlite3_exec() interface runs zero or more UTF-8 encoded,** semicolon-separate SQL statements passed into its 2nd argument,** in the context of the [database connection] passed in as its 1st** argument. ^If the callback function of the 3rd argument to** sqlite3_exec() is not NULL, then it is invoked for each result row** coming out of the evaluated SQL statements. ^The 4th argument to** sqlite3_exec() is relayed through to the 1st argument of each** callback invocation. ^If the callback pointer to sqlite3_exec()** is NULL, then no callback is ever invoked and result rows are** ignored.**** ^If an error occurs while evaluating the SQL statements passed into** sqlite3_exec(), then execution of the current statement stops and** subsequent statements are skipped. ^If the 5th parameter to sqlite3_exec()** is not NULL then any error message is written into memory obtained** from [sqlite3_malloc()] and passed back through the 5th parameter.** To avoid memory leaks, the application should invoke [sqlite3_free()]** on error message strings returned through the 5th parameter of** sqlite3_exec() after the error message string is no longer needed.** ^If the 5th parameter to sqlite3_exec() is not NULL and no errors** occur, then sqlite3_exec() sets the pointer in its 5th parameter to** NULL before returning.**** ^If an sqlite3_exec() callback returns non-zero, the sqlite3_exec()** routine returns SQLITE_ABORT without invoking the callback again and** without running any subsequent SQL statements.**** ^The 2nd argument to the sqlite3_exec() callback function is the** number of columns in the result. ^The 3rd argument to the sqlite3_exec()** callback is an array of pointers to strings obtained as if from** [sqlite3_column_text()], one for each column. ^If an element of a** result row is NULL then the corresponding string pointer for the** sqlite3_exec() callback is a NULL pointer. ^The 4th argument to the** sqlite3_exec() callback is an array of pointers to strings where each** entry represents the name of corresponding result column as obtained** from [sqlite3_column_name()].**** ^If the 2nd parameter to sqlite3_exec() is a NULL pointer, a pointer** to an empty string, or a pointer that contains only whitespace and/or ** SQL comments, then no SQL statements are evaluated and the database** is not changed.**** Restrictions:**** <ul>** <li> The application must ensure that the 1st parameter to sqlite3_exec()** is a valid and open [database connection].** <li> The application must not close the [database connection] specified by** the 1st parameter to sqlite3_exec() while sqlite3_exec() is running.** <li> The application must not modify the SQL statement text passed into** the 2nd parameter of sqlite3_exec() while sqlite3_exec() is running.** </ul>*/SQLITE_APIintsqlite3_exec(sqlite3*,/* An open database */constchar*sql,/* SQL to be evaluated */int(*callback)(void*,int,char**,char**),/* Callback function */void*,/* 1st argument to callback */char**errmsg/* Error msg written here */);/*** CAPI3REF: Result Codes** KEYWORDS: {result code definitions}**** Many SQLite functions return an integer result code from the set shown** here in order to indicate success or failure.**** New error codes may be added in future versions of SQLite.**** See also: [extended result code definitions]*/#define SQLITE_OK 0 /* Successful result *//* beginning-of-error-codes */#define SQLITE_ERROR 1 /* SQL error or missing database */#define SQLITE_INTERNAL 2 /* Internal logic error in SQLite */#define SQLITE_PERM 3 /* Access permission denied */#define SQLITE_ABORT 4 /* Callback routine requested an abort */#define SQLITE_BUSY 5 /* The database file is locked */#define SQLITE_LOCKED 6 /* A table in the database is locked */#define SQLITE_NOMEM 7 /* A malloc() failed */#define SQLITE_READONLY 8 /* Attempt to write a readonly database */#define SQLITE_INTERRUPT 9 /* Operation terminated by sqlite3_interrupt()*/#define SQLITE_IOERR 10 /* Some kind of disk I/O error occurred */#define SQLITE_CORRUPT 11 /* The database disk image is malformed */#define SQLITE_NOTFOUND 12 /* Unknown opcode in sqlite3_file_control() */#define SQLITE_FULL 13 /* Insertion failed because database is full */#define SQLITE_CANTOPEN 14 /* Unable to open the database file */#define SQLITE_PROTOCOL 15 /* Database lock protocol error */#define SQLITE_EMPTY 16 /* Database is empty */#define SQLITE_SCHEMA 17 /* The database schema changed */#define SQLITE_TOOBIG 18 /* String or BLOB exceeds size limit */#define SQLITE_CONSTRAINT 19 /* Abort due to constraint violation */#define SQLITE_MISMATCH 20 /* Data type mismatch */#define SQLITE_MISUSE 21 /* Library used incorrectly */#define SQLITE_NOLFS 22 /* Uses OS features not supported on host */#define SQLITE_AUTH 23 /* Authorization denied */#define SQLITE_FORMAT 24 /* Auxiliary database format error */#define SQLITE_RANGE 25 /* 2nd parameter to sqlite3_bind out of range */#define SQLITE_NOTADB 26 /* File opened that is not a database file */#define SQLITE_NOTICE 27 /* Notifications from sqlite3_log() */#define SQLITE_WARNING 28 /* Warnings from sqlite3_log() */#define SQLITE_ROW 100 /* sqlite3_step() has another row ready */#define SQLITE_DONE 101 /* sqlite3_step() has finished executing *//* end-of-error-codes *//*** CAPI3REF: Extended Result Codes** KEYWORDS: {extended result code definitions}**** In its default configuration, SQLite API routines return one of 30 integer** [result codes]. However, experience has shown that many of** these result codes are too coarse-grained. They do not provide as** much information about problems as programmers might like. In an effort to** address this, newer versions of SQLite (version 3.3.8 [dateof:3.3.8]** and later) include** support for additional result codes that provide more detailed information** about errors. These [extended result codes] are enabled or disabled** on a per database connection basis using the** [sqlite3_extended_result_codes()] API. Or, the extended code for** the most recent error can be obtained using** [sqlite3_extended_errcode()].*/#define SQLITE_IOERR_READ (SQLITE_IOERR | (1<<8))#define SQLITE_IOERR_SHORT_READ (SQLITE_IOERR | (2<<8))#define SQLITE_IOERR_WRITE (SQLITE_IOERR | (3<<8))#define SQLITE_IOERR_FSYNC (SQLITE_IOERR | (4<<8))#define SQLITE_IOERR_DIR_FSYNC (SQLITE_IOERR | (5<<8))#define SQLITE_IOERR_TRUNCATE (SQLITE_IOERR | (6<<8))#define SQLITE_IOERR_FSTAT (SQLITE_IOERR | (7<<8))#define SQLITE_IOERR_UNLOCK (SQLITE_IOERR | (8<<8))#define SQLITE_IOERR_RDLOCK (SQLITE_IOERR | (9<<8))#define SQLITE_IOERR_DELETE (SQLITE_IOERR | (10<<8))#define SQLITE_IOERR_BLOCKED (SQLITE_IOERR | (11<<8))#define SQLITE_IOERR_NOMEM (SQLITE_IOERR | (12<<8))#define SQLITE_IOERR_ACCESS (SQLITE_IOERR | (13<<8))#define SQLITE_IOERR_CHECKRESERVEDLOCK (SQLITE_IOERR | (14<<8))#define SQLITE_IOERR_LOCK (SQLITE_IOERR | (15<<8))#define SQLITE_IOERR_CLOSE (SQLITE_IOERR | (16<<8))#define SQLITE_IOERR_DIR_CLOSE (SQLITE_IOERR | (17<<8))#define SQLITE_IOERR_SHMOPEN (SQLITE_IOERR | (18<<8))#define SQLITE_IOERR_SHMSIZE (SQLITE_IOERR | (19<<8))#define SQLITE_IOERR_SHMLOCK (SQLITE_IOERR | (20<<8))#define SQLITE_IOERR_SHMMAP (SQLITE_IOERR | (21<<8))#define SQLITE_IOERR_SEEK (SQLITE_IOERR | (22<<8))#define SQLITE_IOERR_DELETE_NOENT (SQLITE_IOERR | (23<<8))#define SQLITE_IOERR_MMAP (SQLITE_IOERR | (24<<8))#define SQLITE_IOERR_GETTEMPPATH (SQLITE_IOERR | (25<<8))#define SQLITE_IOERR_CONVPATH (SQLITE_IOERR | (26<<8))#define SQLITE_IOERR_VNODE (SQLITE_IOERR | (27<<8))#define SQLITE_IOERR_AUTH (SQLITE_IOERR | (28<<8))#define SQLITE_LOCKED_SHAREDCACHE (SQLITE_LOCKED | (1<<8))#define SQLITE_BUSY_RECOVERY (SQLITE_BUSY | (1<<8))#define SQLITE_BUSY_SNAPSHOT (SQLITE_BUSY | (2<<8))#define SQLITE_CANTOPEN_NOTEMPDIR (SQLITE_CANTOPEN | (1<<8))#define SQLITE_CANTOPEN_ISDIR (SQLITE_CANTOPEN | (2<<8))#define SQLITE_CANTOPEN_FULLPATH (SQLITE_CANTOPEN | (3<<8))#define SQLITE_CANTOPEN_CONVPATH (SQLITE_CANTOPEN | (4<<8))#define SQLITE_CORRUPT_VTAB (SQLITE_CORRUPT | (1<<8))#define SQLITE_READONLY_RECOVERY (SQLITE_READONLY | (1<<8))#define SQLITE_READONLY_CANTLOCK (SQLITE_READONLY | (2<<8))#define SQLITE_READONLY_ROLLBACK (SQLITE_READONLY | (3<<8))#define SQLITE_READONLY_DBMOVED (SQLITE_READONLY | (4<<8))#define SQLITE_ABORT_ROLLBACK (SQLITE_ABORT | (2<<8))#define SQLITE_CONSTRAINT_CHECK (SQLITE_CONSTRAINT | (1<<8))#define SQLITE_CONSTRAINT_COMMITHOOK (SQLITE_CONSTRAINT | (2<<8))#define SQLITE_CONSTRAINT_FOREIGNKEY (SQLITE_CONSTRAINT | (3<<8))#define SQLITE_CONSTRAINT_FUNCTION (SQLITE_CONSTRAINT | (4<<8))#define SQLITE_CONSTRAINT_NOTNULL (SQLITE_CONSTRAINT | (5<<8))#define SQLITE_CONSTRAINT_PRIMARYKEY (SQLITE_CONSTRAINT | (6<<8))#define SQLITE_CONSTRAINT_TRIGGER (SQLITE_CONSTRAINT | (7<<8))#define SQLITE_CONSTRAINT_UNIQUE (SQLITE_CONSTRAINT | (8<<8))#define SQLITE_CONSTRAINT_VTAB (SQLITE_CONSTRAINT | (9<<8))#define SQLITE_CONSTRAINT_ROWID (SQLITE_CONSTRAINT |(10<<8))#define SQLITE_NOTICE_RECOVER_WAL (SQLITE_NOTICE | (1<<8))#define SQLITE_NOTICE_RECOVER_ROLLBACK (SQLITE_NOTICE | (2<<8))#define SQLITE_WARNING_AUTOINDEX (SQLITE_WARNING | (1<<8))#define SQLITE_AUTH_USER (SQLITE_AUTH | (1<<8))#define SQLITE_OK_LOAD_PERMANENTLY (SQLITE_OK | (1<<8))/*** CAPI3REF: Flags For File Open Operations**** These bit values are intended for use in the** 3rd parameter to the [sqlite3_open_v2()] interface and** in the 4th parameter to the [sqlite3_vfs.xOpen] method.*/#define SQLITE_OPEN_READONLY 0x00000001 /* Ok for sqlite3_open_v2() */#define SQLITE_OPEN_READWRITE 0x00000002 /* Ok for sqlite3_open_v2() */#define SQLITE_OPEN_CREATE 0x00000004 /* Ok for sqlite3_open_v2() */#define SQLITE_OPEN_DELETEONCLOSE 0x00000008 /* VFS only */#define SQLITE_OPEN_EXCLUSIVE 0x00000010 /* VFS only */#define SQLITE_OPEN_AUTOPROXY 0x00000020 /* VFS only */#define SQLITE_OPEN_URI 0x00000040 /* Ok for sqlite3_open_v2() */#define SQLITE_OPEN_MEMORY 0x00000080 /* Ok for sqlite3_open_v2() */#define SQLITE_OPEN_MAIN_DB 0x00000100 /* VFS only */#define SQLITE_OPEN_TEMP_DB 0x00000200 /* VFS only */#define SQLITE_OPEN_TRANSIENT_DB 0x00000400 /* VFS only */#define SQLITE_OPEN_MAIN_JOURNAL 0x00000800 /* VFS only */#define SQLITE_OPEN_TEMP_JOURNAL 0x00001000 /* VFS only */#define SQLITE_OPEN_SUBJOURNAL 0x00002000 /* VFS only */#define SQLITE_OPEN_MASTER_JOURNAL 0x00004000 /* VFS only */#define SQLITE_OPEN_NOMUTEX 0x00008000 /* Ok for sqlite3_open_v2() */#define SQLITE_OPEN_FULLMUTEX 0x00010000 /* Ok for sqlite3_open_v2() */#define SQLITE_OPEN_SHAREDCACHE 0x00020000 /* Ok for sqlite3_open_v2() */#define SQLITE_OPEN_PRIVATECACHE 0x00040000 /* Ok for sqlite3_open_v2() */#define SQLITE_OPEN_WAL 0x00080000 /* VFS only *//* Reserved: 0x00F00000 *//*** CAPI3REF: Device Characteristics**** The xDeviceCharacteristics method of the [sqlite3_io_methods]** object returns an integer which is a vector of these** bit values expressing I/O characteristics of the mass storage** device that holds the file that the [sqlite3_io_methods]** refers to.**** The SQLITE_IOCAP_ATOMIC property means that all writes of** any size are atomic. The SQLITE_IOCAP_ATOMICnnn values** mean that writes of blocks that are nnn bytes in size and** are aligned to an address which is an integer multiple of** nnn are atomic. The SQLITE_IOCAP_SAFE_APPEND value means** that when data is appended to a file, the data is appended** first then the size of the file is extended, never the other** way around. The SQLITE_IOCAP_SEQUENTIAL property means that** information is written to disk in the same order as calls** to xWrite(). The SQLITE_IOCAP_POWERSAFE_OVERWRITE property means that** after reboot following a crash or power loss, the only bytes in a** file that were written at the application level might have changed** and that adjacent bytes, even bytes within the same sector are** guaranteed to be unchanged. The SQLITE_IOCAP_UNDELETABLE_WHEN_OPEN** flag indicate that a file cannot be deleted when open. The** SQLITE_IOCAP_IMMUTABLE flag indicates that the file is on** read-only media and cannot be changed even by processes with** elevated privileges.*/#define SQLITE_IOCAP_ATOMIC 0x00000001#define SQLITE_IOCAP_ATOMIC512 0x00000002#define SQLITE_IOCAP_ATOMIC1K 0x00000004#define SQLITE_IOCAP_ATOMIC2K 0x00000008#define SQLITE_IOCAP_ATOMIC4K 0x00000010#define SQLITE_IOCAP_ATOMIC8K 0x00000020#define SQLITE_IOCAP_ATOMIC16K 0x00000040#define SQLITE_IOCAP_ATOMIC32K 0x00000080#define SQLITE_IOCAP_ATOMIC64K 0x00000100#define SQLITE_IOCAP_SAFE_APPEND 0x00000200#define SQLITE_IOCAP_SEQUENTIAL 0x00000400#define SQLITE_IOCAP_UNDELETABLE_WHEN_OPEN 0x00000800#define SQLITE_IOCAP_POWERSAFE_OVERWRITE 0x00001000#define SQLITE_IOCAP_IMMUTABLE 0x00002000/*** CAPI3REF: File Locking Levels**** SQLite uses one of these integer values as the second** argument to calls it makes to the xLock() and xUnlock() methods** of an [sqlite3_io_methods] object.*/#define SQLITE_LOCK_NONE 0#define SQLITE_LOCK_SHARED 1#define SQLITE_LOCK_RESERVED 2#define SQLITE_LOCK_PENDING 3#define SQLITE_LOCK_EXCLUSIVE 4/*** CAPI3REF: Synchronization Type Flags**** When SQLite invokes the xSync() method of an** [sqlite3_io_methods] object it uses a combination of** these integer values as the second argument.**** When the SQLITE_SYNC_DATAONLY flag is used, it means that the** sync operation only needs to flush data to mass storage. Inode** information need not be flushed. If the lower four bits of the flag** equal SQLITE_SYNC_NORMAL, that means to use normal fsync() semantics.** If the lower four bits equal SQLITE_SYNC_FULL, that means** to use Mac OS X style fullsync instead of fsync().**** Do not confuse the SQLITE_SYNC_NORMAL and SQLITE_SYNC_FULL flags** with the [PRAGMA synchronous]=NORMAL and [PRAGMA synchronous]=FULL** settings. The [synchronous pragma] determines when calls to the** xSync VFS method occur and applies uniformly across all platforms.** The SQLITE_SYNC_NORMAL and SQLITE_SYNC_FULL flags determine how** energetic or rigorous or forceful the sync operations are and** only make a difference on Mac OSX for the default SQLite code.** (Third-party VFS implementations might also make the distinction** between SQLITE_SYNC_NORMAL and SQLITE_SYNC_FULL, but among the** operating systems natively supported by SQLite, only Mac OSX** cares about the difference.)*/#define SQLITE_SYNC_NORMAL 0x00002#define SQLITE_SYNC_FULL 0x00003#define SQLITE_SYNC_DATAONLY 0x00010/*** CAPI3REF: OS Interface Open File Handle**** An [sqlite3_file] object represents an open file in the ** [sqlite3_vfs | OS interface layer]. Individual OS interface** implementations will** want to subclass this object by appending additional fields** for their own use. The pMethods entry is a pointer to an** [sqlite3_io_methods] object that defines methods for performing** I/O operations on the open file.*/typedefstructsqlite3_filesqlite3_file;structsqlite3_file{conststructsqlite3_io_methods*pMethods;/* Methods for an open file */};/*** CAPI3REF: OS Interface File Virtual Methods Object**** Every file opened by the [sqlite3_vfs.xOpen] method populates an** [sqlite3_file] object (or, more commonly, a subclass of the** [sqlite3_file] object) with a pointer to an instance of this object.** This object defines the methods used to perform various operations** against the open file represented by the [sqlite3_file] object.**** If the [sqlite3_vfs.xOpen] method sets the sqlite3_file.pMethods element ** to a non-NULL pointer, then the sqlite3_io_methods.xClose method** may be invoked even if the [sqlite3_vfs.xOpen] reported that it failed. The** only way to prevent a call to xClose following a failed [sqlite3_vfs.xOpen]** is for the [sqlite3_vfs.xOpen] to set the sqlite3_file.pMethods element** to NULL.**** The flags argument to xSync may be one of [SQLITE_SYNC_NORMAL] or** [SQLITE_SYNC_FULL]. The first choice is the normal fsync().** The second choice is a Mac OS X style fullsync. The [SQLITE_SYNC_DATAONLY]** flag may be ORed in to indicate that only the data of the file** and not its inode needs to be synced.**** The integer values to xLock() and xUnlock() are one of** <ul>** <li> [SQLITE_LOCK_NONE],** <li> [SQLITE_LOCK_SHARED],** <li> [SQLITE_LOCK_RESERVED],** <li> [SQLITE_LOCK_PENDING], or** <li> [SQLITE_LOCK_EXCLUSIVE].** </ul>** xLock() increases the lock. xUnlock() decreases the lock.** The xCheckReservedLock() method checks whether any database connection,** either in this process or in some other process, is holding a RESERVED,** PENDING, or EXCLUSIVE lock on the file. It returns true** if such a lock exists and false otherwise.**** The xFileControl() method is a generic interface that allows custom** VFS implementations to directly control an open file using the** [sqlite3_file_control()] interface. The second "op" argument is an** integer opcode. The third argument is a generic pointer intended to** point to a structure that may contain arguments or space in which to** write return values. Potential uses for xFileControl() might be** functions to enable blocking locks with timeouts, to change the** locking strategy (for example to use dot-file locks), to inquire** about the status of a lock, or to break stale locks. The SQLite** core reserves all opcodes less than 100 for its own use.** A [file control opcodes | list of opcodes] less than 100 is available.** Applications that define a custom xFileControl method should use opcodes** greater than 100 to avoid conflicts. VFS implementations should** return [SQLITE_NOTFOUND] for file control opcodes that they do not** recognize.**** The xSectorSize() method returns the sector size of the** device that underlies the file. The sector size is the** minimum write that can be performed without disturbing** other bytes in the file. The xDeviceCharacteristics()** method returns a bit vector describing behaviors of the** underlying device:**** <ul>** <li> [SQLITE_IOCAP_ATOMIC]** <li> [SQLITE_IOCAP_ATOMIC512]** <li> [SQLITE_IOCAP_ATOMIC1K]** <li> [SQLITE_IOCAP_ATOMIC2K]** <li> [SQLITE_IOCAP_ATOMIC4K]** <li> [SQLITE_IOCAP_ATOMIC8K]** <li> [SQLITE_IOCAP_ATOMIC16K]** <li> [SQLITE_IOCAP_ATOMIC32K]** <li> [SQLITE_IOCAP_ATOMIC64K]** <li> [SQLITE_IOCAP_SAFE_APPEND]** <li> [SQLITE_IOCAP_SEQUENTIAL]** </ul>**** The SQLITE_IOCAP_ATOMIC property means that all writes of** any size are atomic. The SQLITE_IOCAP_ATOMICnnn values** mean that writes of blocks that are nnn bytes in size and** are aligned to an address which is an integer multiple of** nnn are atomic. The SQLITE_IOCAP_SAFE_APPEND value means** that when data is appended to a file, the data is appended** first then the size of the file is extended, never the other** way around. The SQLITE_IOCAP_SEQUENTIAL property means that** information is written to disk in the same order as calls** to xWrite().**** If xRead() returns SQLITE_IOERR_SHORT_READ it must also fill** in the unread portions of the buffer with zeros. A VFS that** fails to zero-fill short reads might seem to work. However,** failure to zero-fill short reads will eventually lead to** database corruption.*/typedefstructsqlite3_io_methodssqlite3_io_methods;structsqlite3_io_methods{intiVersion;int(*xClose)(sqlite3_file*);int(*xRead)(sqlite3_file*,void*,intiAmt,sqlite3_int64iOfst);int(*xWrite)(sqlite3_file*,constvoid*,intiAmt,sqlite3_int64iOfst);int(*xTruncate)(sqlite3_file*,sqlite3_int64size);int(*xSync)(sqlite3_file*,intflags);int(*xFileSize)(sqlite3_file*,sqlite3_int64*pSize);int(*xLock)(sqlite3_file*,int);int(*xUnlock)(sqlite3_file*,int);int(*xCheckReservedLock)(sqlite3_file*,int*pResOut);int(*xFileControl)(sqlite3_file*,intop,void*pArg);int(*xSectorSize)(sqlite3_file*);int(*xDeviceCharacteristics)(sqlite3_file*);/* Methods above are valid for version 1 */int(*xShmMap)(sqlite3_file*,intiPg,intpgsz,int,voidvolatile**);int(*xShmLock)(sqlite3_file*,intoffset,intn,intflags);void(*xShmBarrier)(sqlite3_file*);int(*xShmUnmap)(sqlite3_file*,intdeleteFlag);/* Methods above are valid for version 2 */int(*xFetch)(sqlite3_file*,sqlite3_int64iOfst,intiAmt,void**pp);int(*xUnfetch)(sqlite3_file*,sqlite3_int64iOfst,void*p);/* Methods above are valid for version 3 *//* Additional methods may be added in future releases */};/*** CAPI3REF: Standard File Control Opcodes** KEYWORDS: {file control opcodes} {file control opcode}**** These integer constants are opcodes for the xFileControl method** of the [sqlite3_io_methods] object and for the [sqlite3_file_control()]** interface.**** <ul>** <li>[[SQLITE_FCNTL_LOCKSTATE]]** The [SQLITE_FCNTL_LOCKSTATE] opcode is used for debugging. This** opcode causes the xFileControl method to write the current state of** the lock (one of [SQLITE_LOCK_NONE], [SQLITE_LOCK_SHARED],** [SQLITE_LOCK_RESERVED], [SQLITE_LOCK_PENDING], or [SQLITE_LOCK_EXCLUSIVE])** into an integer that the pArg argument points to. This capability** is used during testing and is only available when the SQLITE_TEST** compile-time option is used.**** <li>[[SQLITE_FCNTL_SIZE_HINT]]** The [SQLITE_FCNTL_SIZE_HINT] opcode is used by SQLite to give the VFS** layer a hint of how large the database file will grow to be during the** current transaction. This hint is not guaranteed to be accurate but it** is often close. The underlying VFS might choose to preallocate database** file space based on this hint in order to help writes to the database** file run faster.**** <li>[[SQLITE_FCNTL_CHUNK_SIZE]]** The [SQLITE_FCNTL_CHUNK_SIZE] opcode is used to request that the VFS** extends and truncates the database file in chunks of a size specified** by the user. The fourth argument to [sqlite3_file_control()] should ** point to an integer (type int) containing the new chunk-size to use** for the nominated database. Allocating database file space in large** chunks (say 1MB at a time), may reduce file-system fragmentation and** improve performance on some systems.**** <li>[[SQLITE_FCNTL_FILE_POINTER]]** The [SQLITE_FCNTL_FILE_POINTER] opcode is used to obtain a pointer** to the [sqlite3_file] object associated with a particular database** connection. See also [SQLITE_FCNTL_JOURNAL_POINTER].**** <li>[[SQLITE_FCNTL_JOURNAL_POINTER]]** The [SQLITE_FCNTL_JOURNAL_POINTER] opcode is used to obtain a pointer** to the [sqlite3_file] object associated with the journal file (either** the [rollback journal] or the [write-ahead log]) for a particular database** connection. See also [SQLITE_FCNTL_FILE_POINTER].**** <li>[[SQLITE_FCNTL_SYNC_OMITTED]]** No longer in use.**** <li>[[SQLITE_FCNTL_SYNC]]** The [SQLITE_FCNTL_SYNC] opcode is generated internally by SQLite and** sent to the VFS immediately before the xSync method is invoked on a** database file descriptor. Or, if the xSync method is not invoked ** because the user has configured SQLite with ** [PRAGMA synchronous | PRAGMA synchronous=OFF] it is invoked in place ** of the xSync method. In most cases, the pointer argument passed with** this file-control is NULL. However, if the database file is being synced** as part of a multi-database commit, the argument points to a nul-terminated** string containing the transactions master-journal file name. VFSes that ** do not need this signal should silently ignore this opcode. Applications ** should not call [sqlite3_file_control()] with this opcode as doing so may ** disrupt the operation of the specialized VFSes that do require it. **** <li>[[SQLITE_FCNTL_COMMIT_PHASETWO]]** The [SQLITE_FCNTL_COMMIT_PHASETWO] opcode is generated internally by SQLite** and sent to the VFS after a transaction has been committed immediately** but before the database is unlocked. VFSes that do not need this signal** should silently ignore this opcode. Applications should not call** [sqlite3_file_control()] with this opcode as doing so may disrupt the ** operation of the specialized VFSes that do require it. **** <li>[[SQLITE_FCNTL_WIN32_AV_RETRY]]** ^The [SQLITE_FCNTL_WIN32_AV_RETRY] opcode is used to configure automatic** retry counts and intervals for certain disk I/O operations for the** windows [VFS] in order to provide robustness in the presence of** anti-virus programs. By default, the windows VFS will retry file read,** file write, and file delete operations up to 10 times, with a delay** of 25 milliseconds before the first retry and with the delay increasing** by an additional 25 milliseconds with each subsequent retry. This** opcode allows these two values (10 retries and 25 milliseconds of delay)** to be adjusted. The values are changed for all database connections** within the same process. The argument is a pointer to an array of two** integers where the first integer i the new retry count and the second** integer is the delay. If either integer is negative, then the setting** is not changed but instead the prior value of that setting is written** into the array entry, allowing the current retry settings to be** interrogated. The zDbName parameter is ignored.**** <li>[[SQLITE_FCNTL_PERSIST_WAL]]** ^The [SQLITE_FCNTL_PERSIST_WAL] opcode is used to set or query the** persistent [WAL | Write Ahead Log] setting. By default, the auxiliary** write ahead log and shared memory files used for transaction control** are automatically deleted when the latest connection to the database** closes. Setting persistent WAL mode causes those files to persist after** close. Persisting the files is useful when other processes that do not** have write permission on the directory containing the database file want** to read the database file, as the WAL and shared memory files must exist** in order for the database to be readable. The fourth parameter to** [sqlite3_file_control()] for this opcode should be a pointer to an integer.** That integer is 0 to disable persistent WAL mode or 1 to enable persistent** WAL mode. If the integer is -1, then it is overwritten with the current** WAL persistence setting.**** <li>[[SQLITE_FCNTL_POWERSAFE_OVERWRITE]]** ^The [SQLITE_FCNTL_POWERSAFE_OVERWRITE] opcode is used to set or query the** persistent "powersafe-overwrite" or "PSOW" setting. The PSOW setting** determines the [SQLITE_IOCAP_POWERSAFE_OVERWRITE] bit of the** xDeviceCharacteristics methods. The fourth parameter to** [sqlite3_file_control()] for this opcode should be a pointer to an integer.** That integer is 0 to disable zero-damage mode or 1 to enable zero-damage** mode. If the integer is -1, then it is overwritten with the current** zero-damage mode setting.**** <li>[[SQLITE_FCNTL_OVERWRITE]]** ^The [SQLITE_FCNTL_OVERWRITE] opcode is invoked by SQLite after opening** a write transaction to indicate that, unless it is rolled back for some** reason, the entire database file will be overwritten by the current ** transaction. This is used by VACUUM operations.**** <li>[[SQLITE_FCNTL_VFSNAME]]** ^The [SQLITE_FCNTL_VFSNAME] opcode can be used to obtain the names of** all [VFSes] in the VFS stack. The names are of all VFS shims and the** final bottom-level VFS are written into memory obtained from ** [sqlite3_malloc()] and the result is stored in the char* variable** that the fourth parameter of [sqlite3_file_control()] points to.** The caller is responsible for freeing the memory when done. As with** all file-control actions, there is no guarantee that this will actually** do anything. Callers should initialize the char* variable to a NULL** pointer in case this file-control is not implemented. This file-control** is intended for diagnostic use only.**** <li>[[SQLITE_FCNTL_VFS_POINTER]]** ^The [SQLITE_FCNTL_VFS_POINTER] opcode finds a pointer to the top-level** [VFSes] currently in use. ^(The argument X in** sqlite3_file_control(db,SQLITE_FCNTL_VFS_POINTER,X) must be** of type "[sqlite3_vfs] **". This opcodes will set *X** to a pointer to the top-level VFS.)^** ^When there are multiple VFS shims in the stack, this opcode finds the** upper-most shim only.**** <li>[[SQLITE_FCNTL_PRAGMA]]** ^Whenever a [PRAGMA] statement is parsed, an [SQLITE_FCNTL_PRAGMA] ** file control is sent to the open [sqlite3_file] object corresponding** to the database file to which the pragma statement refers. ^The argument** to the [SQLITE_FCNTL_PRAGMA] file control is an array of** pointers to strings (char**) in which the second element of the array** is the name of the pragma and the third element is the argument to the** pragma or NULL if the pragma has no argument. ^The handler for an** [SQLITE_FCNTL_PRAGMA] file control can optionally make the first element** of the char** argument point to a string obtained from [sqlite3_mprintf()]** or the equivalent and that string will become the result of the pragma or** the error message if the pragma fails. ^If the** [SQLITE_FCNTL_PRAGMA] file control returns [SQLITE_NOTFOUND], then normal ** [PRAGMA] processing continues. ^If the [SQLITE_FCNTL_PRAGMA]** file control returns [SQLITE_OK], then the parser assumes that the** VFS has handled the PRAGMA itself and the parser generates a no-op** prepared statement if result string is NULL, or that returns a copy** of the result string if the string is non-NULL.** ^If the [SQLITE_FCNTL_PRAGMA] file control returns** any result code other than [SQLITE_OK] or [SQLITE_NOTFOUND], that means** that the VFS encountered an error while handling the [PRAGMA] and the** compilation of the PRAGMA fails with an error. ^The [SQLITE_FCNTL_PRAGMA]** file control occurs at the beginning of pragma statement analysis and so** it is able to override built-in [PRAGMA] statements.**** <li>[[SQLITE_FCNTL_BUSYHANDLER]]** ^The [SQLITE_FCNTL_BUSYHANDLER]** file-control may be invoked by SQLite on the database file handle** shortly after it is opened in order to provide a custom VFS with access** to the connections busy-handler callback. The argument is of type (void **)** - an array of two (void *) values. The first (void *) actually points** to a function of type (int (*)(void *)). In order to invoke the connections** busy-handler, this function should be invoked with the second (void *) in** the array as the only argument. If it returns non-zero, then the operation** should be retried. If it returns zero, the custom VFS should abandon the** current operation.**** <li>[[SQLITE_FCNTL_TEMPFILENAME]]** ^Application can invoke the [SQLITE_FCNTL_TEMPFILENAME] file-control** to have SQLite generate a** temporary filename using the same algorithm that is followed to generate** temporary filenames for TEMP tables and other internal uses. The** argument should be a char** which will be filled with the filename** written into memory obtained from [sqlite3_malloc()]. The caller should** invoke [sqlite3_free()] on the result to avoid a memory leak.**** <li>[[SQLITE_FCNTL_MMAP_SIZE]]** The [SQLITE_FCNTL_MMAP_SIZE] file control is used to query or set the** maximum number of bytes that will be used for memory-mapped I/O.** The argument is a pointer to a value of type sqlite3_int64 that** is an advisory maximum number of bytes in the file to memory map. The** pointer is overwritten with the old value. The limit is not changed if** the value originally pointed to is negative, and so the current limit ** can be queried by passing in a pointer to a negative number. This** file-control is used internally to implement [PRAGMA mmap_size].**** <li>[[SQLITE_FCNTL_TRACE]]** The [SQLITE_FCNTL_TRACE] file control provides advisory information** to the VFS about what the higher layers of the SQLite stack are doing.** This file control is used by some VFS activity tracing [shims].** The argument is a zero-terminated string. Higher layers in the** SQLite stack may generate instances of this file control if** the [SQLITE_USE_FCNTL_TRACE] compile-time option is enabled.**** <li>[[SQLITE_FCNTL_HAS_MOVED]]** The [SQLITE_FCNTL_HAS_MOVED] file control interprets its argument as a** pointer to an integer and it writes a boolean into that integer depending** on whether or not the file has been renamed, moved, or deleted since it** was first opened.**** <li>[[SQLITE_FCNTL_WIN32_GET_HANDLE]]** The [SQLITE_FCNTL_WIN32_GET_HANDLE] opcode can be used to obtain the** underlying native file handle associated with a file handle. This file** control interprets its argument as a pointer to a native file handle and** writes the resulting value there.**** <li>[[SQLITE_FCNTL_WIN32_SET_HANDLE]]** The [SQLITE_FCNTL_WIN32_SET_HANDLE] opcode is used for debugging. This** opcode causes the xFileControl method to swap the file handle with the one** pointed to by the pArg argument. This capability is used during testing** and only needs to be supported when SQLITE_TEST is defined.**** <li>[[SQLITE_FCNTL_WAL_BLOCK]]** The [SQLITE_FCNTL_WAL_BLOCK] is a signal to the VFS layer that it might** be advantageous to block on the next WAL lock if the lock is not immediately** available. The WAL subsystem issues this signal during rare** circumstances in order to fix a problem with priority inversion.** Applications should <em>not</em> use this file-control.**** <li>[[SQLITE_FCNTL_ZIPVFS]]** The [SQLITE_FCNTL_ZIPVFS] opcode is implemented by zipvfs only. All other** VFS should return SQLITE_NOTFOUND for this opcode.**** <li>[[SQLITE_FCNTL_RBU]]** The [SQLITE_FCNTL_RBU] opcode is implemented by the special VFS used by** the RBU extension only. All other VFS should return SQLITE_NOTFOUND for** this opcode. ** </ul>*/#define SQLITE_FCNTL_LOCKSTATE 1#define SQLITE_FCNTL_GET_LOCKPROXYFILE 2#define SQLITE_FCNTL_SET_LOCKPROXYFILE 3#define SQLITE_FCNTL_LAST_ERRNO 4#define SQLITE_FCNTL_SIZE_HINT 5#define SQLITE_FCNTL_CHUNK_SIZE 6#define SQLITE_FCNTL_FILE_POINTER 7#define SQLITE_FCNTL_SYNC_OMITTED 8#define SQLITE_FCNTL_WIN32_AV_RETRY 9#define SQLITE_FCNTL_PERSIST_WAL 10#define SQLITE_FCNTL_OVERWRITE 11#define SQLITE_FCNTL_VFSNAME 12#define SQLITE_FCNTL_POWERSAFE_OVERWRITE 13#define SQLITE_FCNTL_PRAGMA 14#define SQLITE_FCNTL_BUSYHANDLER 15#define SQLITE_FCNTL_TEMPFILENAME 16#define SQLITE_FCNTL_MMAP_SIZE 18#define SQLITE_FCNTL_TRACE 19#define SQLITE_FCNTL_HAS_MOVED 20#define SQLITE_FCNTL_SYNC 21#define SQLITE_FCNTL_COMMIT_PHASETWO 22#define SQLITE_FCNTL_WIN32_SET_HANDLE 23#define SQLITE_FCNTL_WAL_BLOCK 24#define SQLITE_FCNTL_ZIPVFS 25#define SQLITE_FCNTL_RBU 26#define SQLITE_FCNTL_VFS_POINTER 27#define SQLITE_FCNTL_JOURNAL_POINTER 28#define SQLITE_FCNTL_WIN32_GET_HANDLE 29/* deprecated names */#define SQLITE_GET_LOCKPROXYFILE SQLITE_FCNTL_GET_LOCKPROXYFILE#define SQLITE_SET_LOCKPROXYFILE SQLITE_FCNTL_SET_LOCKPROXYFILE#define SQLITE_LAST_ERRNO SQLITE_FCNTL_LAST_ERRNO/*** CAPI3REF: Mutex Handle**** The mutex module within SQLite defines [sqlite3_mutex] to be an** abstract type for a mutex object. The SQLite core never looks** at the internal representation of an [sqlite3_mutex]. It only** deals with pointers to the [sqlite3_mutex] object.**** Mutexes are created using [sqlite3_mutex_alloc()].*/typedefstructsqlite3_mutexsqlite3_mutex;/*** CAPI3REF: Loadable Extension Thunk**** A pointer to the opaque sqlite3_api_routines structure is passed as** the third parameter to entry points of [loadable extensions]. This** structure must be typedefed in order to work around compiler warnings** on some platforms.*/typedefstructsqlite3_api_routinessqlite3_api_routines;/*** CAPI3REF: OS Interface Object**** An instance of the sqlite3_vfs object defines the interface between** the SQLite core and the underlying operating system. The "vfs"** in the name of the object stands for "virtual file system". See** the [VFS | VFS documentation] for further information.**** The value of the iVersion field is initially 1 but may be larger in** future versions of SQLite. Additional fields may be appended to this** object when the iVersion value is increased. Note that the structure** of the sqlite3_vfs object changes in the transaction between** SQLite version 3.5.9 and 3.6.0 and yet the iVersion field was not** modified.**** The szOsFile field is the size of the subclassed [sqlite3_file]** structure used by this VFS. mxPathname is the maximum length of** a pathname in this VFS.**** Registered sqlite3_vfs objects are kept on a linked list formed by** the pNext pointer. The [sqlite3_vfs_register()]** and [sqlite3_vfs_unregister()] interfaces manage this list** in a thread-safe way. The [sqlite3_vfs_find()] interface** searches the list. Neither the application code nor the VFS** implementation should use the pNext pointer.**** The pNext field is the only field in the sqlite3_vfs** structure that SQLite will ever modify. SQLite will only access** or modify this field while holding a particular static mutex.** The application should never modify anything within the sqlite3_vfs** object once the object has been registered.**** The zName field holds the name of the VFS module. The name must** be unique across all VFS modules.**** [[sqlite3_vfs.xOpen]]** ^SQLite guarantees that the zFilename parameter to xOpen** is either a NULL pointer or string obtained** from xFullPathname() with an optional suffix added.** ^If a suffix is added to the zFilename parameter, it will** consist of a single "-" character followed by no more than** 11 alphanumeric and/or "-" characters.** ^SQLite further guarantees that** the string will be valid and unchanged until xClose() is** called. Because of the previous sentence,** the [sqlite3_file] can safely store a pointer to the** filename if it needs to remember the filename for some reason.** If the zFilename parameter to xOpen is a NULL pointer then xOpen** must invent its own temporary name for the file. ^Whenever the ** xFilename parameter is NULL it will also be the case that the** flags parameter will include [SQLITE_OPEN_DELETEONCLOSE].**** The flags argument to xOpen() includes all bits set in** the flags argument to [sqlite3_open_v2()]. Or if [sqlite3_open()]** or [sqlite3_open16()] is used, then flags includes at least** [SQLITE_OPEN_READWRITE] | [SQLITE_OPEN_CREATE]. ** If xOpen() opens a file read-only then it sets *pOutFlags to** include [SQLITE_OPEN_READONLY]. Other bits in *pOutFlags may be set.**** ^(SQLite will also add one of the following flags to the xOpen()** call, depending on the object being opened:**** <ul>** <li> [SQLITE_OPEN_MAIN_DB]** <li> [SQLITE_OPEN_MAIN_JOURNAL]** <li> [SQLITE_OPEN_TEMP_DB]** <li> [SQLITE_OPEN_TEMP_JOURNAL]** <li> [SQLITE_OPEN_TRANSIENT_DB]** <li> [SQLITE_OPEN_SUBJOURNAL]** <li> [SQLITE_OPEN_MASTER_JOURNAL]** <li> [SQLITE_OPEN_WAL]** </ul>)^**** The file I/O implementation can use the object type flags to** change the way it deals with files. For example, an application** that does not care about crash recovery or rollback might make** the open of a journal file a no-op. Writes to this journal would** also be no-ops, and any attempt to read the journal would return** SQLITE_IOERR. Or the implementation might recognize that a database** file will be doing page-aligned sector reads and writes in a random** order and set up its I/O subsystem accordingly.**** SQLite might also add one of the following flags to the xOpen method:**** <ul>** <li> [SQLITE_OPEN_DELETEONCLOSE]** <li> [SQLITE_OPEN_EXCLUSIVE]** </ul>**** The [SQLITE_OPEN_DELETEONCLOSE] flag means the file should be** deleted when it is closed. ^The [SQLITE_OPEN_DELETEONCLOSE]** will be set for TEMP databases and their journals, transient** databases, and subjournals.**** ^The [SQLITE_OPEN_EXCLUSIVE] flag is always used in conjunction** with the [SQLITE_OPEN_CREATE] flag, which are both directly** analogous to the O_EXCL and O_CREAT flags of the POSIX open()** API. The SQLITE_OPEN_EXCLUSIVE flag, when paired with the ** SQLITE_OPEN_CREATE, is used to indicate that file should always** be created, and that it is an error if it already exists.** It is <i>not</i> used to indicate the file should be opened ** for exclusive access.**** ^At least szOsFile bytes of memory are allocated by SQLite** to hold the [sqlite3_file] structure passed as the third** argument to xOpen. The xOpen method does not have to** allocate the structure; it should just fill it in. Note that** the xOpen method must set the sqlite3_file.pMethods to either** a valid [sqlite3_io_methods] object or to NULL. xOpen must do** this even if the open fails. SQLite expects that the sqlite3_file.pMethods** element will be valid after xOpen returns regardless of the success** or failure of the xOpen call.**** [[sqlite3_vfs.xAccess]]** ^The flags argument to xAccess() may be [SQLITE_ACCESS_EXISTS]** to test for the existence of a file, or [SQLITE_ACCESS_READWRITE] to** test whether a file is readable and writable, or [SQLITE_ACCESS_READ]** to test whether a file is at least readable. The file can be a** directory.**** ^SQLite will always allocate at least mxPathname+1 bytes for the** output buffer xFullPathname. The exact size of the output buffer** is also passed as a parameter to both methods. If the output buffer** is not large enough, [SQLITE_CANTOPEN] should be returned. Since this is** handled as a fatal error by SQLite, vfs implementations should endeavor** to prevent this by setting mxPathname to a sufficiently large value.**** The xRandomness(), xSleep(), xCurrentTime(), and xCurrentTimeInt64()** interfaces are not strictly a part of the filesystem, but they are** included in the VFS structure for completeness.** The xRandomness() function attempts to return nBytes bytes** of good-quality randomness into zOut. The return value is** the actual number of bytes of randomness obtained.** The xSleep() method causes the calling thread to sleep for at** least the number of microseconds given. ^The xCurrentTime()** method returns a Julian Day Number for the current date and time as** a floating point value.** ^The xCurrentTimeInt64() method returns, as an integer, the Julian** Day Number multiplied by 86400000 (the number of milliseconds in ** a 24-hour day). ** ^SQLite will use the xCurrentTimeInt64() method to get the current** date and time if that method is available (if iVersion is 2 or ** greater and the function pointer is not NULL) and will fall back** to xCurrentTime() if xCurrentTimeInt64() is unavailable.**** ^The xSetSystemCall(), xGetSystemCall(), and xNestSystemCall() interfaces** are not used by the SQLite core. These optional interfaces are provided** by some VFSes to facilitate testing of the VFS code. By overriding ** system calls with functions under its control, a test program can** simulate faults and error conditions that would otherwise be difficult** or impossible to induce. The set of system calls that can be overridden** varies from one VFS to another, and from one version of the same VFS to the** next. Applications that use these interfaces must be prepared for any** or all of these interfaces to be NULL or for their behavior to change** from one release to the next. Applications must not attempt to access** any of these methods if the iVersion of the VFS is less than 3.*/typedefstructsqlite3_vfssqlite3_vfs;typedefvoid(*sqlite3_syscall_ptr)(void);structsqlite3_vfs{intiVersion;/* Structure version number (currently 3) */intszOsFile;/* Size of subclassed sqlite3_file */intmxPathname;/* Maximum file pathname length */sqlite3_vfs*pNext;/* Next registered VFS */constchar*zName;/* Name of this virtual file system */void*pAppData;/* Pointer to application-specific data */int(*xOpen)(sqlite3_vfs*,constchar*zName,sqlite3_file*,intflags,int*pOutFlags);int(*xDelete)(sqlite3_vfs*,constchar*zName,intsyncDir);int(*xAccess)(sqlite3_vfs*,constchar*zName,intflags,int*pResOut);int(*xFullPathname)(sqlite3_vfs*,constchar*zName,intnOut,char*zOut);void*(*xDlOpen)(sqlite3_vfs*,constchar*zFilename);void(*xDlError)(sqlite3_vfs*,intnByte,char*zErrMsg);void(*(*xDlSym)(sqlite3_vfs*,void*,constchar*zSymbol))(void);void(*xDlClose)(sqlite3_vfs*,void*);int(*xRandomness)(sqlite3_vfs*,intnByte,char*zOut);int(*xSleep)(sqlite3_vfs*,intmicroseconds);int(*xCurrentTime)(sqlite3_vfs*,double*);int(*xGetLastError)(sqlite3_vfs*,int,char*);/* ** The methods above are in version 1 of the sqlite_vfs object ** definition. Those that follow are added in version 2 or later */int(*xCurrentTimeInt64)(sqlite3_vfs*,sqlite3_int64*);/* ** The methods above are in versions 1 and 2 of the sqlite_vfs object. ** Those below are for version 3 and greater. */int(*xSetSystemCall)(sqlite3_vfs*,constchar*zName,sqlite3_syscall_ptr);sqlite3_syscall_ptr(*xGetSystemCall)(sqlite3_vfs*,constchar*zName);constchar*(*xNextSystemCall)(sqlite3_vfs*,constchar*zName);/* ** The methods above are in versions 1 through 3 of the sqlite_vfs object. ** New fields may be appended in future versions. The iVersion ** value will increment whenever this happens. */};/*** CAPI3REF: Flags for the xAccess VFS method**** These integer constants can be used as the third parameter to** the xAccess method of an [sqlite3_vfs] object. They determine** what kind of permissions the xAccess method is looking for.** With SQLITE_ACCESS_EXISTS, the xAccess method** simply checks whether the file exists.** With SQLITE_ACCESS_READWRITE, the xAccess method** checks whether the named directory is both readable and writable** (in other words, if files can be added, removed, and renamed within** the directory).** The SQLITE_ACCESS_READWRITE constant is currently used only by the** [temp_store_directory pragma], though this could change in a future** release of SQLite.** With SQLITE_ACCESS_READ, the xAccess method** checks whether the file is readable. The SQLITE_ACCESS_READ constant is** currently unused, though it might be used in a future release of** SQLite.*/#define SQLITE_ACCESS_EXISTS 0#define SQLITE_ACCESS_READWRITE 1 /* Used by PRAGMA temp_store_directory */#define SQLITE_ACCESS_READ 2 /* Unused *//*** CAPI3REF: Flags for the xShmLock VFS method**** These integer constants define the various locking operations** allowed by the xShmLock method of [sqlite3_io_methods]. The** following are the only legal combinations of flags to the** xShmLock method:**** <ul>** <li> SQLITE_SHM_LOCK | SQLITE_SHM_SHARED** <li> SQLITE_SHM_LOCK | SQLITE_SHM_EXCLUSIVE** <li> SQLITE_SHM_UNLOCK | SQLITE_SHM_SHARED** <li> SQLITE_SHM_UNLOCK | SQLITE_SHM_EXCLUSIVE** </ul>**** When unlocking, the same SHARED or EXCLUSIVE flag must be supplied as** was given on the corresponding lock. **** The xShmLock method can transition between unlocked and SHARED or** between unlocked and EXCLUSIVE. It cannot transition between SHARED** and EXCLUSIVE.*/#define SQLITE_SHM_UNLOCK 1#define SQLITE_SHM_LOCK 2#define SQLITE_SHM_SHARED 4#define SQLITE_SHM_EXCLUSIVE 8/*** CAPI3REF: Maximum xShmLock index**** The xShmLock method on [sqlite3_io_methods] may use values** between 0 and this upper bound as its "offset" argument.** The SQLite core will never attempt to acquire or release a** lock outside of this range*/#define SQLITE_SHM_NLOCK 8/*** CAPI3REF: Initialize The SQLite Library**** ^The sqlite3_initialize() routine initializes the** SQLite library. ^The sqlite3_shutdown() routine** deallocates any resources that were allocated by sqlite3_initialize().** These routines are designed to aid in process initialization and** shutdown on embedded systems. Workstation applications using** SQLite normally do not need to invoke either of these routines.**** A call to sqlite3_initialize() is an "effective" call if it is** the first time sqlite3_initialize() is invoked during the lifetime of** the process, or if it is the first time sqlite3_initialize() is invoked** following a call to sqlite3_shutdown(). ^(Only an effective call** of sqlite3_initialize() does any initialization. All other calls** are harmless no-ops.)^**** A call to sqlite3_shutdown() is an "effective" call if it is the first** call to sqlite3_shutdown() since the last sqlite3_initialize(). ^(Only** an effective call to sqlite3_shutdown() does any deinitialization.** All other valid calls to sqlite3_shutdown() are harmless no-ops.)^**** The sqlite3_initialize() interface is threadsafe, but sqlite3_shutdown()** is not. The sqlite3_shutdown() interface must only be called from a** single thread. All open [database connections] must be closed and all** other SQLite resources must be deallocated prior to invoking** sqlite3_shutdown().**** Among other things, ^sqlite3_initialize() will invoke** sqlite3_os_init(). Similarly, ^sqlite3_shutdown()** will invoke sqlite3_os_end().**** ^The sqlite3_initialize() routine returns [SQLITE_OK] on success.** ^If for some reason, sqlite3_initialize() is unable to initialize** the library (perhaps it is unable to allocate a needed resource such** as a mutex) it returns an [error code] other than [SQLITE_OK].**** ^The sqlite3_initialize() routine is called internally by many other** SQLite interfaces so that an application usually does not need to** invoke sqlite3_initialize() directly. For example, [sqlite3_open()]** calls sqlite3_initialize() so the SQLite library will be automatically** initialized when [sqlite3_open()] is called if it has not be initialized** already. ^However, if SQLite is compiled with the [SQLITE_OMIT_AUTOINIT]** compile-time option, then the automatic calls to sqlite3_initialize()** are omitted and the application must call sqlite3_initialize() directly** prior to using any other SQLite interface. For maximum portability,** it is recommended that applications always invoke sqlite3_initialize()** directly prior to using any other SQLite interface. Future releases** of SQLite may require this. In other words, the behavior exhibited** when SQLite is compiled with [SQLITE_OMIT_AUTOINIT] might become the** default behavior in some future release of SQLite.**** The sqlite3_os_init() routine does operating-system specific** initialization of the SQLite library. The sqlite3_os_end()** routine undoes the effect of sqlite3_os_init(). Typical tasks** performed by these routines include allocation or deallocation** of static resources, initialization of global variables,** setting up a default [sqlite3_vfs] module, or setting up** a default configuration using [sqlite3_config()].**** The application should never invoke either sqlite3_os_init()** or sqlite3_os_end() directly. The application should only invoke** sqlite3_initialize() and sqlite3_shutdown(). The sqlite3_os_init()** interface is called automatically by sqlite3_initialize() and** sqlite3_os_end() is called by sqlite3_shutdown(). Appropriate** implementations for sqlite3_os_init() and sqlite3_os_end()** are built into SQLite when it is compiled for Unix, Windows, or OS/2.** When [custom builds | built for other platforms]** (using the [SQLITE_OS_OTHER=1] compile-time** option) the application must supply a suitable implementation for** sqlite3_os_init() and sqlite3_os_end(). An application-supplied** implementation of sqlite3_os_init() or sqlite3_os_end()** must return [SQLITE_OK] on success and some other [error code] upon** failure.*/SQLITE_APIintsqlite3_initialize(void);SQLITE_APIintsqlite3_shutdown(void);SQLITE_APIintsqlite3_os_init(void);SQLITE_APIintsqlite3_os_end(void);/*** CAPI3REF: Configuring The SQLite Library**** The sqlite3_config() interface is used to make global configuration** changes to SQLite in order to tune SQLite to the specific needs of** the application. The default configuration is recommended for most** applications and so this routine is usually not necessary. It is** provided to support rare applications with unusual needs.**** <b>The sqlite3_config() interface is not threadsafe. The application** must ensure that no other SQLite interfaces are invoked by other** threads while sqlite3_config() is running.</b>**** The sqlite3_config() interface** may only be invoked prior to library initialization using** [sqlite3_initialize()] or after shutdown by [sqlite3_shutdown()].** ^If sqlite3_config() is called after [sqlite3_initialize()] and before** [sqlite3_shutdown()] then it will return SQLITE_MISUSE.** Note, however, that ^sqlite3_config() can be called as part of the** implementation of an application-defined [sqlite3_os_init()].**** The first argument to sqlite3_config() is an integer** [configuration option] that determines** what property of SQLite is to be configured. Subsequent arguments** vary depending on the [configuration option]** in the first argument.**** ^When a configuration option is set, sqlite3_config() returns [SQLITE_OK].** ^If the option is unknown or SQLite is unable to set the option** then this routine returns a non-zero [error code].*/SQLITE_APIintsqlite3_config(int,...);/*** CAPI3REF: Configure database connections** METHOD: sqlite3**** The sqlite3_db_config() interface is used to make configuration** changes to a [database connection]. The interface is similar to** [sqlite3_config()] except that the changes apply to a single** [database connection] (specified in the first argument).**** The second argument to sqlite3_db_config(D,V,...) is the** [SQLITE_DBCONFIG_LOOKASIDE | configuration verb] - an integer code ** that indicates what aspect of the [database connection] is being configured.** Subsequent arguments vary depending on the configuration verb.**** ^Calls to sqlite3_db_config() return SQLITE_OK if and only if** the call is considered successful.*/SQLITE_APIintsqlite3_db_config(sqlite3*,intop,...);/*** CAPI3REF: Memory Allocation Routines**** An instance of this object defines the interface between SQLite** and low-level memory allocation routines.**** This object is used in only one place in the SQLite interface.** A pointer to an instance of this object is the argument to** [sqlite3_config()] when the configuration option is** [SQLITE_CONFIG_MALLOC] or [SQLITE_CONFIG_GETMALLOC]. ** By creating an instance of this object** and passing it to [sqlite3_config]([SQLITE_CONFIG_MALLOC])** during configuration, an application can specify an alternative** memory allocation subsystem for SQLite to use for all of its** dynamic memory needs.**** Note that SQLite comes with several [built-in memory allocators]** that are perfectly adequate for the overwhelming majority of applications** and that this object is only useful to a tiny minority of applications** with specialized memory allocation requirements. This object is** also used during testing of SQLite in order to specify an alternative** memory allocator that simulates memory out-of-memory conditions in** order to verify that SQLite recovers gracefully from such** conditions.**** The xMalloc, xRealloc, and xFree methods must work like the** malloc(), realloc() and free() functions from the standard C library.** ^SQLite guarantees that the second argument to** xRealloc is always a value returned by a prior call to xRoundup.**** xSize should return the allocated size of a memory allocation** previously obtained from xMalloc or xRealloc. The allocated size** is always at least as big as the requested size but may be larger.**** The xRoundup method returns what would be the allocated size of** a memory allocation given a particular requested size. Most memory** allocators round up memory allocations at least to the next multiple** of 8. Some allocators round up to a larger multiple or to a power of 2.** Every memory allocation request coming in through [sqlite3_malloc()]** or [sqlite3_realloc()] first calls xRoundup. If xRoundup returns 0, ** that causes the corresponding memory allocation to fail.**** The xInit method initializes the memory allocator. For example,** it might allocate any require mutexes or initialize internal data** structures. The xShutdown method is invoked (indirectly) by** [sqlite3_shutdown()] and should deallocate any resources acquired** by xInit. The pAppData pointer is used as the only parameter to** xInit and xShutdown.**** SQLite holds the [SQLITE_MUTEX_STATIC_MASTER] mutex when it invokes** the xInit method, so the xInit method need not be threadsafe. The** xShutdown method is only called from [sqlite3_shutdown()] so it does** not need to be threadsafe either. For all other methods, SQLite** holds the [SQLITE_MUTEX_STATIC_MEM] mutex as long as the** [SQLITE_CONFIG_MEMSTATUS] configuration option is turned on (which** it is by default) and so the methods are automatically serialized.** However, if [SQLITE_CONFIG_MEMSTATUS] is disabled, then the other** methods must be threadsafe or else make their own arrangements for** serialization.**** SQLite will never invoke xInit() more than once without an intervening** call to xShutdown().*/typedefstructsqlite3_mem_methodssqlite3_mem_methods;structsqlite3_mem_methods{void*(*xMalloc)(int);/* Memory allocation function */void(*xFree)(void*);/* Free a prior allocation */void*(*xRealloc)(void*,int);/* Resize an allocation */int(*xSize)(void*);/* Return the size of an allocation */int(*xRoundup)(int);/* Round up request size to allocation size */int(*xInit)(void*);/* Initialize the memory allocator */void(*xShutdown)(void*);/* Deinitialize the memory allocator */void*pAppData;/* Argument to xInit() and xShutdown() */};/*** CAPI3REF: Configuration Options** KEYWORDS: {configuration option}**** These constants are the available integer configuration options that** can be passed as the first argument to the [sqlite3_config()] interface.**** New configuration options may be added in future releases of SQLite.** Existing configuration options might be discontinued. Applications** should check the return code from [sqlite3_config()] to make sure that** the call worked. The [sqlite3_config()] interface will return a** non-zero [error code] if a discontinued or unsupported configuration option** is invoked.**** <dl>** [[SQLITE_CONFIG_SINGLETHREAD]] <dt>SQLITE_CONFIG_SINGLETHREAD</dt>** <dd>There are no arguments to this option. ^This option sets the** [threading mode] to Single-thread. In other words, it disables** all mutexing and puts SQLite into a mode where it can only be used** by a single thread. ^If SQLite is compiled with** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then** it is not possible to change the [threading mode] from its default** value of Single-thread and so [sqlite3_config()] will return ** [SQLITE_ERROR] if called with the SQLITE_CONFIG_SINGLETHREAD** configuration option.</dd>**** [[SQLITE_CONFIG_MULTITHREAD]] <dt>SQLITE_CONFIG_MULTITHREAD</dt>** <dd>There are no arguments to this option. ^This option sets the** [threading mode] to Multi-thread. In other words, it disables** mutexing on [database connection] and [prepared statement] objects.** The application is responsible for serializing access to** [database connections] and [prepared statements]. But other mutexes** are enabled so that SQLite will be safe to use in a multi-threaded** environment as long as no two threads attempt to use the same** [database connection] at the same time. ^If SQLite is compiled with** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then** it is not possible to set the Multi-thread [threading mode] and** [sqlite3_config()] will return [SQLITE_ERROR] if called with the** SQLITE_CONFIG_MULTITHREAD configuration option.</dd>**** [[SQLITE_CONFIG_SERIALIZED]] <dt>SQLITE_CONFIG_SERIALIZED</dt>** <dd>There are no arguments to this option. ^This option sets the** [threading mode] to Serialized. In other words, this option enables** all mutexes including the recursive** mutexes on [database connection] and [prepared statement] objects.** In this mode (which is the default when SQLite is compiled with** [SQLITE_THREADSAFE=1]) the SQLite library will itself serialize access** to [database connections] and [prepared statements] so that the** application is free to use the same [database connection] or the** same [prepared statement] in different threads at the same time.** ^If SQLite is compiled with** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then** it is not possible to set the Serialized [threading mode] and** [sqlite3_config()] will return [SQLITE_ERROR] if called with the** SQLITE_CONFIG_SERIALIZED configuration option.</dd>**** [[SQLITE_CONFIG_MALLOC]] <dt>SQLITE_CONFIG_MALLOC</dt>** <dd> ^(The SQLITE_CONFIG_MALLOC option takes a single argument which is ** a pointer to an instance of the [sqlite3_mem_methods] structure.** The argument specifies** alternative low-level memory allocation routines to be used in place of** the memory allocation routines built into SQLite.)^ ^SQLite makes** its own private copy of the content of the [sqlite3_mem_methods] structure** before the [sqlite3_config()] call returns.</dd>**** [[SQLITE_CONFIG_GETMALLOC]] <dt>SQLITE_CONFIG_GETMALLOC</dt>** <dd> ^(The SQLITE_CONFIG_GETMALLOC option takes a single argument which** is a pointer to an instance of the [sqlite3_mem_methods] structure.** The [sqlite3_mem_methods]** structure is filled with the currently defined memory allocation routines.)^** This option can be used to overload the default memory allocation** routines with a wrapper that simulations memory allocation failure or** tracks memory usage, for example. </dd>**** [[SQLITE_CONFIG_MEMSTATUS]] <dt>SQLITE_CONFIG_MEMSTATUS</dt>** <dd> ^The SQLITE_CONFIG_MEMSTATUS option takes single argument of type int,** interpreted as a boolean, which enables or disables the collection of** memory allocation statistics. ^(When memory allocation statistics are** disabled, the following SQLite interfaces become non-operational:** <ul>** <li> [sqlite3_memory_used()]** <li> [sqlite3_memory_highwater()]** <li> [sqlite3_soft_heap_limit64()]** <li> [sqlite3_status64()]** </ul>)^** ^Memory allocation statistics are enabled by default unless SQLite is** compiled with [SQLITE_DEFAULT_MEMSTATUS]=0 in which case memory** allocation statistics are disabled by default.** </dd>**** [[SQLITE_CONFIG_SCRATCH]] <dt>SQLITE_CONFIG_SCRATCH</dt>** <dd> ^The SQLITE_CONFIG_SCRATCH option specifies a static memory buffer** that SQLite can use for scratch memory. ^(There are three arguments** to SQLITE_CONFIG_SCRATCH: A pointer an 8-byte** aligned memory buffer from which the scratch allocations will be** drawn, the size of each scratch allocation (sz),** and the maximum number of scratch allocations (N).)^** The first argument must be a pointer to an 8-byte aligned buffer** of at least sz*N bytes of memory.** ^SQLite will not use more than one scratch buffers per thread.** ^SQLite will never request a scratch buffer that is more than 6** times the database page size.** ^If SQLite needs needs additional** scratch memory beyond what is provided by this configuration option, then ** [sqlite3_malloc()] will be used to obtain the memory needed.<p>** ^When the application provides any amount of scratch memory using** SQLITE_CONFIG_SCRATCH, SQLite avoids unnecessary large** [sqlite3_malloc|heap allocations].** This can help [Robson proof|prevent memory allocation failures] due to heap** fragmentation in low-memory embedded systems.** </dd>**** [[SQLITE_CONFIG_PAGECACHE]] <dt>SQLITE_CONFIG_PAGECACHE</dt>** <dd> ^The SQLITE_CONFIG_PAGECACHE option specifies a memory pool** that SQLite can use for the database page cache with the default page** cache implementation. ** This configuration option is a no-op if an application-define page** cache implementation is loaded using the [SQLITE_CONFIG_PCACHE2].** ^There are three arguments to SQLITE_CONFIG_PAGECACHE: A pointer to** 8-byte aligned memory (pMem), the size of each page cache line (sz),** and the number of cache lines (N).** The sz argument should be the size of the largest database page** (a power of two between 512 and 65536) plus some extra bytes for each** page header. ^The number of extra bytes needed by the page header** can be determined using [SQLITE_CONFIG_PCACHE_HDRSZ].** ^It is harmless, apart from the wasted memory,** for the sz parameter to be larger than necessary. The pMem** argument must be either a NULL pointer or a pointer to an 8-byte** aligned block of memory of at least sz*N bytes, otherwise** subsequent behavior is undefined.** ^When pMem is not NULL, SQLite will strive to use the memory provided** to satisfy page cache needs, falling back to [sqlite3_malloc()] if** a page cache line is larger than sz bytes or if all of the pMem buffer** is exhausted.** ^If pMem is NULL and N is non-zero, then each database connection** does an initial bulk allocation for page cache memory** from [sqlite3_malloc()] sufficient for N cache lines if N is positive or** of -1024*N bytes if N is negative, . ^If additional** page cache memory is needed beyond what is provided by the initial** allocation, then SQLite goes to [sqlite3_malloc()] separately for each** additional cache line. </dd>**** [[SQLITE_CONFIG_HEAP]] <dt>SQLITE_CONFIG_HEAP</dt>** <dd> ^The SQLITE_CONFIG_HEAP option specifies a static memory buffer ** that SQLite will use for all of its dynamic memory allocation needs** beyond those provided for by [SQLITE_CONFIG_SCRATCH] and** [SQLITE_CONFIG_PAGECACHE].** ^The SQLITE_CONFIG_HEAP option is only available if SQLite is compiled** with either [SQLITE_ENABLE_MEMSYS3] or [SQLITE_ENABLE_MEMSYS5] and returns** [SQLITE_ERROR] if invoked otherwise.** ^There are three arguments to SQLITE_CONFIG_HEAP:** An 8-byte aligned pointer to the memory,** the number of bytes in the memory buffer, and the minimum allocation size.** ^If the first pointer (the memory pointer) is NULL, then SQLite reverts** to using its default memory allocator (the system malloc() implementation),** undoing any prior invocation of [SQLITE_CONFIG_MALLOC]. ^If the** memory pointer is not NULL then the alternative memory** allocator is engaged to handle all of SQLites memory allocation needs.** The first pointer (the memory pointer) must be aligned to an 8-byte** boundary or subsequent behavior of SQLite will be undefined.** The minimum allocation size is capped at 2**12. Reasonable values** for the minimum allocation size are 2**5 through 2**8.</dd>**** [[SQLITE_CONFIG_MUTEX]] <dt>SQLITE_CONFIG_MUTEX</dt>** <dd> ^(The SQLITE_CONFIG_MUTEX option takes a single argument which is a** pointer to an instance of the [sqlite3_mutex_methods] structure.** The argument specifies alternative low-level mutex routines to be used** in place the mutex routines built into SQLite.)^ ^SQLite makes a copy of** the content of the [sqlite3_mutex_methods] structure before the call to** [sqlite3_config()] returns. ^If SQLite is compiled with** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then** the entire mutexing subsystem is omitted from the build and hence calls to** [sqlite3_config()] with the SQLITE_CONFIG_MUTEX configuration option will** return [SQLITE_ERROR].</dd>**** [[SQLITE_CONFIG_GETMUTEX]] <dt>SQLITE_CONFIG_GETMUTEX</dt>** <dd> ^(The SQLITE_CONFIG_GETMUTEX option takes a single argument which** is a pointer to an instance of the [sqlite3_mutex_methods] structure. The** [sqlite3_mutex_methods]** structure is filled with the currently defined mutex routines.)^** This option can be used to overload the default mutex allocation** routines with a wrapper used to track mutex usage for performance** profiling or testing, for example. ^If SQLite is compiled with** the [SQLITE_THREADSAFE | SQLITE_THREADSAFE=0] compile-time option then** the entire mutexing subsystem is omitted from the build and hence calls to** [sqlite3_config()] with the SQLITE_CONFIG_GETMUTEX configuration option will** return [SQLITE_ERROR].</dd>**** [[SQLITE_CONFIG_LOOKASIDE]] <dt>SQLITE_CONFIG_LOOKASIDE</dt>** <dd> ^(The SQLITE_CONFIG_LOOKASIDE option takes two arguments that determine** the default size of lookaside memory on each [database connection].** The first argument is the** size of each lookaside buffer slot and the second is the number of** slots allocated to each database connection.)^ ^(SQLITE_CONFIG_LOOKASIDE** sets the <i>default</i> lookaside size. The [SQLITE_DBCONFIG_LOOKASIDE]** option to [sqlite3_db_config()] can be used to change the lookaside** configuration on individual connections.)^ </dd>**** [[SQLITE_CONFIG_PCACHE2]] <dt>SQLITE_CONFIG_PCACHE2</dt>** <dd> ^(The SQLITE_CONFIG_PCACHE2 option takes a single argument which is ** a pointer to an [sqlite3_pcache_methods2] object. This object specifies** the interface to a custom page cache implementation.)^** ^SQLite makes a copy of the [sqlite3_pcache_methods2] object.</dd>**** [[SQLITE_CONFIG_GETPCACHE2]] <dt>SQLITE_CONFIG_GETPCACHE2</dt>** <dd> ^(The SQLITE_CONFIG_GETPCACHE2 option takes a single argument which** is a pointer to an [sqlite3_pcache_methods2] object. SQLite copies of** the current page cache implementation into that object.)^ </dd>**** [[SQLITE_CONFIG_LOG]] <dt>SQLITE_CONFIG_LOG</dt>** <dd> The SQLITE_CONFIG_LOG option is used to configure the SQLite** global [error log].** (^The SQLITE_CONFIG_LOG option takes two arguments: a pointer to a** function with a call signature of void(*)(void*,int,const char*), ** and a pointer to void. ^If the function pointer is not NULL, it is** invoked by [sqlite3_log()] to process each logging event. ^If the** function pointer is NULL, the [sqlite3_log()] interface becomes a no-op.** ^The void pointer that is the second argument to SQLITE_CONFIG_LOG is** passed through as the first parameter to the application-defined logger** function whenever that function is invoked. ^The second parameter to** the logger function is a copy of the first parameter to the corresponding** [sqlite3_log()] call and is intended to be a [result code] or an** [extended result code]. ^The third parameter passed to the logger is** log message after formatting via [sqlite3_snprintf()].** The SQLite logging interface is not reentrant; the logger function** supplied by the application must not invoke any SQLite interface.** In a multi-threaded application, the application-defined logger** function must be threadsafe. </dd>**** [[SQLITE_CONFIG_URI]] <dt>SQLITE_CONFIG_URI** <dd>^(The SQLITE_CONFIG_URI option takes a single argument of type int.** If non-zero, then URI handling is globally enabled. If the parameter is zero,** then URI handling is globally disabled.)^ ^If URI handling is globally** enabled, all filenames passed to [sqlite3_open()], [sqlite3_open_v2()],** [sqlite3_open16()] or** specified as part of [ATTACH] commands are interpreted as URIs, regardless** of whether or not the [SQLITE_OPEN_URI] flag is set when the database** connection is opened. ^If it is globally disabled, filenames are** only interpreted as URIs if the SQLITE_OPEN_URI flag is set when the** database connection is opened. ^(By default, URI handling is globally** disabled. The default value may be changed by compiling with the** [SQLITE_USE_URI] symbol defined.)^**** [[SQLITE_CONFIG_COVERING_INDEX_SCAN]] <dt>SQLITE_CONFIG_COVERING_INDEX_SCAN** <dd>^The SQLITE_CONFIG_COVERING_INDEX_SCAN option takes a single integer** argument which is interpreted as a boolean in order to enable or disable** the use of covering indices for full table scans in the query optimizer.** ^The default setting is determined** by the [SQLITE_ALLOW_COVERING_INDEX_SCAN] compile-time option, or is "on"** if that compile-time option is omitted.** The ability to disable the use of covering indices for full table scans** is because some incorrectly coded legacy applications might malfunction** when the optimization is enabled. Providing the ability to** disable the optimization allows the older, buggy application code to work** without change even with newer versions of SQLite.**** [[SQLITE_CONFIG_PCACHE]] [[SQLITE_CONFIG_GETPCACHE]]** <dt>SQLITE_CONFIG_PCACHE and SQLITE_CONFIG_GETPCACHE** <dd> These options are obsolete and should not be used by new code.** They are retained for backwards compatibility but are now no-ops.** </dd>**** [[SQLITE_CONFIG_SQLLOG]]** <dt>SQLITE_CONFIG_SQLLOG** <dd>This option is only available if sqlite is compiled with the** [SQLITE_ENABLE_SQLLOG] pre-processor macro defined. The first argument should** be a pointer to a function of type void(*)(void*,sqlite3*,const char*, int).** The second should be of type (void*). The callback is invoked by the library** in three separate circumstances, identified by the value passed as the** fourth parameter. If the fourth parameter is 0, then the database connection** passed as the second argument has just been opened. The third argument** points to a buffer containing the name of the main database file. If the** fourth parameter is 1, then the SQL statement that the third parameter** points to has just been executed. Or, if the fourth parameter is 2, then** the connection being passed as the second parameter is being closed. The** third parameter is passed NULL In this case. An example of using this** configuration option can be seen in the "test_sqllog.c" source file in** the canonical SQLite source tree.</dd>**** [[SQLITE_CONFIG_MMAP_SIZE]]** <dt>SQLITE_CONFIG_MMAP_SIZE** <dd>^SQLITE_CONFIG_MMAP_SIZE takes two 64-bit integer (sqlite3_int64) values** that are the default mmap size limit (the default setting for** [PRAGMA mmap_size]) and the maximum allowed mmap size limit.** ^The default setting can be overridden by each database connection using** either the [PRAGMA mmap_size] command, or by using the** [SQLITE_FCNTL_MMAP_SIZE] file control. ^(The maximum allowed mmap size** will be silently truncated if necessary so that it does not exceed the** compile-time maximum mmap size set by the** [SQLITE_MAX_MMAP_SIZE] compile-time option.)^** ^If either argument to this option is negative, then that argument is** changed to its compile-time default.**** [[SQLITE_CONFIG_WIN32_HEAPSIZE]]** <dt>SQLITE_CONFIG_WIN32_HEAPSIZE** <dd>^The SQLITE_CONFIG_WIN32_HEAPSIZE option is only available if SQLite is** compiled for Windows with the [SQLITE_WIN32_MALLOC] pre-processor macro** defined. ^SQLITE_CONFIG_WIN32_HEAPSIZE takes a 32-bit unsigned integer value** that specifies the maximum size of the created heap.**** [[SQLITE_CONFIG_PCACHE_HDRSZ]]** <dt>SQLITE_CONFIG_PCACHE_HDRSZ** <dd>^The SQLITE_CONFIG_PCACHE_HDRSZ option takes a single parameter which** is a pointer to an integer and writes into that integer the number of extra** bytes per page required for each page in [SQLITE_CONFIG_PAGECACHE].** The amount of extra space required can change depending on the compiler,** target platform, and SQLite version.**** [[SQLITE_CONFIG_PMASZ]]** <dt>SQLITE_CONFIG_PMASZ** <dd>^The SQLITE_CONFIG_PMASZ option takes a single parameter which** is an unsigned integer and sets the "Minimum PMA Size" for the multithreaded** sorter to that integer. The default minimum PMA Size is set by the** [SQLITE_SORTER_PMASZ] compile-time option. New threads are launched** to help with sort operations when multithreaded sorting** is enabled (using the [PRAGMA threads] command) and the amount of content** to be sorted exceeds the page size times the minimum of the** [PRAGMA cache_size] setting and this value.**** [[SQLITE_CONFIG_STMTJRNL_SPILL]]** <dt>SQLITE_CONFIG_STMTJRNL_SPILL** <dd>^The SQLITE_CONFIG_STMTJRNL_SPILL option takes a single parameter which** becomes the [statement journal] spill-to-disk threshold. ** [Statement journals] are held in memory until their size (in bytes)** exceeds this threshold, at which point they are written to disk.** Or if the threshold is -1, statement journals are always held** exclusively in memory.** Since many statement journals never become large, setting the spill** threshold to a value such as 64KiB can greatly reduce the amount of** I/O required to support statement rollback.** The default value for this setting is controlled by the** [SQLITE_STMTJRNL_SPILL] compile-time option.** </dl>*/#define SQLITE_CONFIG_SINGLETHREAD 1 /* nil */#define SQLITE_CONFIG_MULTITHREAD 2 /* nil */#define SQLITE_CONFIG_SERIALIZED 3 /* nil */#define SQLITE_CONFIG_MALLOC 4 /* sqlite3_mem_methods* */#define SQLITE_CONFIG_GETMALLOC 5 /* sqlite3_mem_methods* */#define SQLITE_CONFIG_SCRATCH 6 /* void*, int sz, int N */#define SQLITE_CONFIG_PAGECACHE 7 /* void*, int sz, int N */#define SQLITE_CONFIG_HEAP 8 /* void*, int nByte, int min */#define SQLITE_CONFIG_MEMSTATUS 9 /* boolean */#define SQLITE_CONFIG_MUTEX 10 /* sqlite3_mutex_methods* */#define SQLITE_CONFIG_GETMUTEX 11 /* sqlite3_mutex_methods* *//* previously SQLITE_CONFIG_CHUNKALLOC 12 which is now unused. */#define SQLITE_CONFIG_LOOKASIDE 13 /* int int */#define SQLITE_CONFIG_PCACHE 14 /* no-op */#define SQLITE_CONFIG_GETPCACHE 15 /* no-op */#define SQLITE_CONFIG_LOG 16 /* xFunc, void* */#define SQLITE_CONFIG_URI 17 /* int */#define SQLITE_CONFIG_PCACHE2 18 /* sqlite3_pcache_methods2* */#define SQLITE_CONFIG_GETPCACHE2 19 /* sqlite3_pcache_methods2* */#define SQLITE_CONFIG_COVERING_INDEX_SCAN 20 /* int */#define SQLITE_CONFIG_SQLLOG 21 /* xSqllog, void* */#define SQLITE_CONFIG_MMAP_SIZE 22 /* sqlite3_int64, sqlite3_int64 */#define SQLITE_CONFIG_WIN32_HEAPSIZE 23 /* int nByte */#define SQLITE_CONFIG_PCACHE_HDRSZ 24 /* int *psz */#define SQLITE_CONFIG_PMASZ 25 /* unsigned int szPma */#define SQLITE_CONFIG_STMTJRNL_SPILL 26 /* int nByte *//*** CAPI3REF: Database Connection Configuration Options**** These constants are the available integer configuration options that** can be passed as the second argument to the [sqlite3_db_config()] interface.**** New configuration options may be added in future releases of SQLite.** Existing configuration options might be discontinued. Applications** should check the return code from [sqlite3_db_config()] to make sure that** the call worked. ^The [sqlite3_db_config()] interface will return a** non-zero [error code] if a discontinued or unsupported configuration option** is invoked.**** <dl>** <dt>SQLITE_DBCONFIG_LOOKASIDE</dt>** <dd> ^This option takes three additional arguments that determine the ** [lookaside memory allocator] configuration for the [database connection].** ^The first argument (the third parameter to [sqlite3_db_config()] is a** pointer to a memory buffer to use for lookaside memory.** ^The first argument after the SQLITE_DBCONFIG_LOOKASIDE verb** may be NULL in which case SQLite will allocate the** lookaside buffer itself using [sqlite3_malloc()]. ^The second argument is the** size of each lookaside buffer slot. ^The third argument is the number of** slots. The size of the buffer in the first argument must be greater than** or equal to the product of the second and third arguments. The buffer** must be aligned to an 8-byte boundary. ^If the second argument to** SQLITE_DBCONFIG_LOOKASIDE is not a multiple of 8, it is internally** rounded down to the next smaller multiple of 8. ^(The lookaside memory** configuration for a database connection can only be changed when that** connection is not currently using lookaside memory, or in other words** when the "current value" returned by** [sqlite3_db_status](D,[SQLITE_CONFIG_LOOKASIDE],...) is zero.** Any attempt to change the lookaside memory configuration when lookaside** memory is in use leaves the configuration unchanged and returns ** [SQLITE_BUSY].)^</dd>**** <dt>SQLITE_DBCONFIG_ENABLE_FKEY</dt>** <dd> ^This option is used to enable or disable the enforcement of** [foreign key constraints]. There should be two additional arguments.** The first argument is an integer which is 0 to disable FK enforcement,** positive to enable FK enforcement or negative to leave FK enforcement** unchanged. The second parameter is a pointer to an integer into which** is written 0 or 1 to indicate whether FK enforcement is off or on** following this call. The second parameter may be a NULL pointer, in** which case the FK enforcement setting is not reported back. </dd>**** <dt>SQLITE_DBCONFIG_ENABLE_TRIGGER</dt>** <dd> ^This option is used to enable or disable [CREATE TRIGGER | triggers].** There should be two additional arguments.** The first argument is an integer which is 0 to disable triggers,** positive to enable triggers or negative to leave the setting unchanged.** The second parameter is a pointer to an integer into which** is written 0 or 1 to indicate whether triggers are disabled or enabled** following this call. The second parameter may be a NULL pointer, in** which case the trigger setting is not reported back. </dd>**** <dt>SQLITE_DBCONFIG_ENABLE_FTS3_TOKENIZER</dt>** <dd> ^This option is used to enable or disable the two-argument** version of the [fts3_tokenizer()] function which is part of the** [FTS3] full-text search engine extension.** There should be two additional arguments.** The first argument is an integer which is 0 to disable fts3_tokenizer() or** positive to enable fts3_tokenizer() or negative to leave the setting** unchanged.** The second parameter is a pointer to an integer into which** is written 0 or 1 to indicate whether fts3_tokenizer is disabled or enabled** following this call. The second parameter may be a NULL pointer, in** which case the new setting is not reported back. </dd>**** <dt>SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION</dt>** <dd> ^This option is used to enable or disable the [sqlite3_load_extension()]** interface independently of the [load_extension()] SQL function.** The [sqlite3_enable_load_extension()] API enables or disables both the** C-API [sqlite3_load_extension()] and the SQL function [load_extension()].** There should be two additional arguments.** When the first argument to this interface is 1, then only the C-API is** enabled and the SQL function remains disabled. If the first argument to** this interface is 0, then both the C-API and the SQL function are disabled.** If the first argument is -1, then no changes are made to state of either the** C-API or the SQL function.** The second parameter is a pointer to an integer into which** is written 0 or 1 to indicate whether [sqlite3_load_extension()] interface** is disabled or enabled following this call. The second parameter may** be a NULL pointer, in which case the new setting is not reported back.** </dd>**** <dt>SQLITE_DBCONFIG_MAINDBNAME</dt>** <dd> ^This option is used to change the name of the "main" database** schema. ^The sole argument is a pointer to a constant UTF8 string** which will become the new schema name in place of "main". ^SQLite** does not make a copy of the new main schema name string, so the application** must ensure that the argument passed into this DBCONFIG option is unchanged** until after the database connection closes.** </dd>**** </dl>*/#define SQLITE_DBCONFIG_MAINDBNAME 1000 /* const char* */#define SQLITE_DBCONFIG_LOOKASIDE 1001 /* void* int int */#define SQLITE_DBCONFIG_ENABLE_FKEY 1002 /* int int* */#define SQLITE_DBCONFIG_ENABLE_TRIGGER 1003 /* int int* */#define SQLITE_DBCONFIG_ENABLE_FTS3_TOKENIZER 1004 /* int int* */#define SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION 1005 /* int int* *//*** CAPI3REF: Enable Or Disable Extended Result Codes** METHOD: sqlite3**** ^The sqlite3_extended_result_codes() routine enables or disables the** [extended result codes] feature of SQLite. ^The extended result** codes are disabled by default for historical compatibility.*/SQLITE_APIintsqlite3_extended_result_codes(sqlite3*,intonoff);/*** CAPI3REF: Last Insert Rowid** METHOD: sqlite3**** ^Each entry in most SQLite tables (except for [WITHOUT ROWID] tables)** has a unique 64-bit signed** integer key called the [ROWID | "rowid"]. ^The rowid is always available** as an undeclared column named ROWID, OID, or _ROWID_ as long as those** names are not also used by explicitly declared columns. ^If** the table has a column of type [INTEGER PRIMARY KEY] then that column** is another alias for the rowid.**** ^The sqlite3_last_insert_rowid(D) interface returns the [rowid] of the ** most recent successful [INSERT] into a rowid table or [virtual table]** on database connection D.** ^Inserts into [WITHOUT ROWID] tables are not recorded.** ^If no successful [INSERT]s into rowid tables** have ever occurred on the database connection D, ** then sqlite3_last_insert_rowid(D) returns zero.**** ^(If an [INSERT] occurs within a trigger or within a [virtual table]** method, then this routine will return the [rowid] of the inserted** row as long as the trigger or virtual table method is running.** But once the trigger or virtual table method ends, the value returned ** by this routine reverts to what it was before the trigger or virtual** table method began.)^**** ^An [INSERT] that fails due to a constraint violation is not a** successful [INSERT] and does not change the value returned by this** routine. ^Thus INSERT OR FAIL, INSERT OR IGNORE, INSERT OR ROLLBACK,** and INSERT OR ABORT make no changes to the return value of this** routine when their insertion fails. ^(When INSERT OR REPLACE** encounters a constraint violation, it does not fail. The** INSERT continues to completion after deleting rows that caused** the constraint problem so INSERT OR REPLACE will always change** the return value of this interface.)^**** ^For the purposes of this routine, an [INSERT] is considered to** be successful even if it is subsequently rolled back.**** This function is accessible to SQL statements via the** [last_insert_rowid() SQL function].**** If a separate thread performs a new [INSERT] on the same** database connection while the [sqlite3_last_insert_rowid()]** function is running and thus changes the last insert [rowid],** then the value returned by [sqlite3_last_insert_rowid()] is** unpredictable and might not equal either the old or the new** last insert [rowid].*/SQLITE_APIsqlite3_int64sqlite3_last_insert_rowid(sqlite3*);/*** CAPI3REF: Count The Number Of Rows Modified** METHOD: sqlite3**** ^This function returns the number of rows modified, inserted or** deleted by the most recently completed INSERT, UPDATE or DELETE** statement on the database connection specified by the only parameter.** ^Executing any other type of SQL statement does not modify the value** returned by this function.**** ^Only changes made directly by the INSERT, UPDATE or DELETE statement are** considered - auxiliary changes caused by [CREATE TRIGGER | triggers], ** [foreign key actions] or [REPLACE] constraint resolution are not counted.** ** Changes to a view that are intercepted by ** [INSTEAD OF trigger | INSTEAD OF triggers] are not counted. ^The value ** returned by sqlite3_changes() immediately after an INSERT, UPDATE or ** DELETE statement run on a view is always zero. Only changes made to real ** tables are counted.**** Things are more complicated if the sqlite3_changes() function is** executed while a trigger program is running. This may happen if the** program uses the [changes() SQL function], or if some other callback** function invokes sqlite3_changes() directly. Essentially:** ** <ul>** <li> ^(Before entering a trigger program the value returned by** sqlite3_changes() function is saved. After the trigger program ** has finished, the original value is restored.)^** ** <li> ^(Within a trigger program each INSERT, UPDATE and DELETE ** statement sets the value returned by sqlite3_changes() ** upon completion as normal. Of course, this value will not include ** any changes performed by sub-triggers, as the sqlite3_changes() ** value will be saved and restored after each sub-trigger has run.)^** </ul>** ** ^This means that if the changes() SQL function (or similar) is used** by the first INSERT, UPDATE or DELETE statement within a trigger, it ** returns the value as set when the calling statement began executing.** ^If it is used by the second or subsequent such statement within a trigger ** program, the value returned reflects the number of rows modified by the ** previous INSERT, UPDATE or DELETE statement within the same trigger.**** See also the [sqlite3_total_changes()] interface, the** [count_changes pragma], and the [changes() SQL function].**** If a separate thread makes changes on the same database connection** while [sqlite3_changes()] is running then the value returned** is unpredictable and not meaningful.*/SQLITE_APIintsqlite3_changes(sqlite3*);/*** CAPI3REF: Total Number Of Rows Modified** METHOD: sqlite3**** ^This function returns the total number of rows inserted, modified or** deleted by all [INSERT], [UPDATE] or [DELETE] statements completed** since the database connection was opened, including those executed as** part of trigger programs. ^Executing any other type of SQL statement** does not affect the value returned by sqlite3_total_changes().** ** ^Changes made as part of [foreign key actions] are included in the** count, but those made as part of REPLACE constraint resolution are** not. ^Changes to a view that are intercepted by INSTEAD OF triggers ** are not counted.** ** See also the [sqlite3_changes()] interface, the** [count_changes pragma], and the [total_changes() SQL function].**** If a separate thread makes changes on the same database connection** while [sqlite3_total_changes()] is running then the value** returned is unpredictable and not meaningful.*/SQLITE_APIintsqlite3_total_changes(sqlite3*);/*** CAPI3REF: Interrupt A Long-Running Query** METHOD: sqlite3**** ^This function causes any pending database operation to abort and** return at its earliest opportunity. This routine is typically** called in response to a user action such as pressing "Cancel"** or Ctrl-C where the user wants a long query operation to halt** immediately.**** ^It is safe to call this routine from a thread different from the** thread that is currently running the database operation. But it** is not safe to call this routine with a [database connection] that** is closed or might close before sqlite3_interrupt() returns.**** ^If an SQL operation is very nearly finished at the time when** sqlite3_interrupt() is called, then it might not have an opportunity** to be interrupted and might continue to completion.**** ^An SQL operation that is interrupted will return [SQLITE_INTERRUPT].** ^If the interrupted SQL operation is an INSERT, UPDATE, or DELETE** that is inside an explicit transaction, then the entire transaction** will be rolled back automatically.**** ^The sqlite3_interrupt(D) call is in effect until all currently running** SQL statements on [database connection] D complete. ^Any new SQL statements** that are started after the sqlite3_interrupt() call and before the ** running statements reaches zero are interrupted as if they had been** running prior to the sqlite3_interrupt() call. ^New SQL statements** that are started after the running statement count reaches zero are** not effected by the sqlite3_interrupt().** ^A call to sqlite3_interrupt(D) that occurs when there are no running** SQL statements is a no-op and has no effect on SQL statements** that are started after the sqlite3_interrupt() call returns.**** If the database connection closes while [sqlite3_interrupt()]** is running then bad things will likely happen.*/SQLITE_APIvoidsqlite3_interrupt(sqlite3*);/*** CAPI3REF: Determine If An SQL Statement Is Complete**** These routines are useful during command-line input to determine if the** currently entered text seems to form a complete SQL statement or** if additional input is needed before sending the text into** SQLite for parsing. ^These routines return 1 if the input string** appears to be a complete SQL statement. ^A statement is judged to be** complete if it ends with a semicolon token and is not a prefix of a** well-formed CREATE TRIGGER statement. ^Semicolons that are embedded within** string literals or quoted identifier names or comments are not** independent tokens (they are part of the token in which they are** embedded) and thus do not count as a statement terminator. ^Whitespace** and comments that follow the final semicolon are ignored.**** ^These routines return 0 if the statement is incomplete. ^If a** memory allocation fails, then SQLITE_NOMEM is returned.**** ^These routines do not parse the SQL statements thus** will not detect syntactically incorrect SQL.**** ^(If SQLite has not been initialized using [sqlite3_initialize()] prior ** to invoking sqlite3_complete16() then sqlite3_initialize() is invoked** automatically by sqlite3_complete16(). If that initialization fails,** then the return value from sqlite3_complete16() will be non-zero** regardless of whether or not the input SQL is complete.)^**** The input to [sqlite3_complete()] must be a zero-terminated** UTF-8 string.**** The input to [sqlite3_complete16()] must be a zero-terminated** UTF-16 string in native byte order.*/SQLITE_APIintsqlite3_complete(constchar*sql);SQLITE_APIintsqlite3_complete16(constvoid*sql);/*** CAPI3REF: Register A Callback To Handle SQLITE_BUSY Errors** KEYWORDS: {busy-handler callback} {busy handler}** METHOD: sqlite3**** ^The sqlite3_busy_handler(D,X,P) routine sets a callback function X** that might be invoked with argument P whenever** an attempt is made to access a database table associated with** [database connection] D when another thread** or process has the table locked.** The sqlite3_busy_handler() interface is used to implement** [sqlite3_busy_timeout()] and [PRAGMA busy_timeout].**** ^If the busy callback is NULL, then [SQLITE_BUSY]** is returned immediately upon encountering the lock. ^If the busy callback** is not NULL, then the callback might be invoked with two arguments.**** ^The first argument to the busy handler is a copy of the void* pointer which** is the third argument to sqlite3_busy_handler(). ^The second argument to** the busy handler callback is the number of times that the busy handler has** been invoked previously for the same locking event. ^If the** busy callback returns 0, then no additional attempts are made to** access the database and [SQLITE_BUSY] is returned** to the application.** ^If the callback returns non-zero, then another attempt** is made to access the database and the cycle repeats.**** The presence of a busy handler does not guarantee that it will be invoked** when there is lock contention. ^If SQLite determines that invoking the busy** handler could result in a deadlock, it will go ahead and return [SQLITE_BUSY]** to the application instead of invoking the ** busy handler.** Consider a scenario where one process is holding a read lock that** it is trying to promote to a reserved lock and** a second process is holding a reserved lock that it is trying** to promote to an exclusive lock. The first process cannot proceed** because it is blocked by the second and the second process cannot** proceed because it is blocked by the first. If both processes** invoke the busy handlers, neither will make any progress. Therefore,** SQLite returns [SQLITE_BUSY] for the first process, hoping that this** will induce the first process to release its read lock and allow** the second process to proceed.**** ^The default busy callback is NULL.**** ^(There can only be a single busy handler defined for each** [database connection]. Setting a new busy handler clears any** previously set handler.)^ ^Note that calling [sqlite3_busy_timeout()]** or evaluating [PRAGMA busy_timeout=N] will change the** busy handler and thus clear any previously set busy handler.**** The busy callback should not take any actions which modify the** database connection that invoked the busy handler. In other words,** the busy handler is not reentrant. Any such actions** result in undefined behavior.** ** A busy handler must not close the database connection** or [prepared statement] that invoked the busy handler.*/SQLITE_APIintsqlite3_busy_handler(sqlite3*,int(*)(void*,int),void*);/*** CAPI3REF: Set A Busy Timeout** METHOD: sqlite3**** ^This routine sets a [sqlite3_busy_handler | busy handler] that sleeps** for a specified amount of time when a table is locked. ^The handler** will sleep multiple times until at least "ms" milliseconds of sleeping** have accumulated. ^After at least "ms" milliseconds of sleeping,** the handler returns 0 which causes [sqlite3_step()] to return** [SQLITE_BUSY].**** ^Calling this routine with an argument less than or equal to zero** turns off all busy handlers.**** ^(There can only be a single busy handler for a particular** [database connection] at any given moment. If another busy handler** was defined (using [sqlite3_busy_handler()]) prior to calling** this routine, that other busy handler is cleared.)^**** See also: [PRAGMA busy_timeout]*/SQLITE_APIintsqlite3_busy_timeout(sqlite3*,intms);/*** CAPI3REF: Convenience Routines For Running Queries** METHOD: sqlite3**** This is a legacy interface that is preserved for backwards compatibility.** Use of this interface is not recommended.**** Definition: A <b>result table</b> is memory data structure created by the** [sqlite3_get_table()] interface. A result table records the** complete query results from one or more queries.**** The table conceptually has a number of rows and columns. But** these numbers are not part of the result table itself. These** numbers are obtained separately. Let N be the number of rows** and M be the number of columns.**** A result table is an array of pointers to zero-terminated UTF-8 strings.** There are (N+1)*M elements in the array. The first M pointers point** to zero-terminated strings that contain the names of the columns.** The remaining entries all point to query results. NULL values result** in NULL pointers. All other values are in their UTF-8 zero-terminated** string representation as returned by [sqlite3_column_text()].**** A result table might consist of one or more memory allocations.** It is not safe to pass a result table directly to [sqlite3_free()].** A result table should be deallocated using [sqlite3_free_table()].**** ^(As an example of the result table format, suppose a query result** is as follows:**** <blockquote><pre>** Name | Age** -----------------------** Alice | 43** Bob | 28** Cindy | 21** </pre></blockquote>**** There are two column (M==2) and three rows (N==3). Thus the** result table has 8 entries. Suppose the result table is stored** in an array names azResult. Then azResult holds this content:**** <blockquote><pre>** azResult[0] = "Name";** azResult[1] = "Age";** azResult[2] = "Alice";** azResult[3] = "43";** azResult[4] = "Bob";** azResult[5] = "28";** azResult[6] = "Cindy";** azResult[7] = "21";** </pre></blockquote>)^**** ^The sqlite3_get_table() function evaluates one or more** semicolon-separated SQL statements in the zero-terminated UTF-8** string of its 2nd parameter and returns a result table to the** pointer given in its 3rd parameter.**** After the application has finished with the result from sqlite3_get_table(),** it must pass the result table pointer to sqlite3_free_table() in order to** release the memory that was malloced. Because of the way the** [sqlite3_malloc()] happens within sqlite3_get_table(), the calling** function must not try to call [sqlite3_free()] directly. Only** [sqlite3_free_table()] is able to release the memory properly and safely.**** The sqlite3_get_table() interface is implemented as a wrapper around** [sqlite3_exec()]. The sqlite3_get_table() routine does not have access** to any internal data structures of SQLite. It uses only the public** interface defined here. As a consequence, errors that occur in the** wrapper layer outside of the internal [sqlite3_exec()] call are not** reflected in subsequent calls to [sqlite3_errcode()] or** [sqlite3_errmsg()].*/SQLITE_APIintsqlite3_get_table(sqlite3*db,/* An open database */constchar*zSql,/* SQL to be evaluated */char***pazResult,/* Results of the query */int*pnRow,/* Number of result rows written here */int*pnColumn,/* Number of result columns written here */char**pzErrmsg/* Error msg written here */);SQLITE_APIvoidsqlite3_free_table(char**result);/*** CAPI3REF: Formatted String Printing Functions**** These routines are work-alikes of the "printf()" family of functions** from the standard C library.** These routines understand most of the common K&R formatting options,** plus some additional non-standard formats, detailed below.** Note that some of the more obscure formatting options from recent** C-library standards are omitted from this implementation.**** ^The sqlite3_mprintf() and sqlite3_vmprintf() routines write their** results into memory obtained from [sqlite3_malloc()].** The strings returned by these two routines should be** released by [sqlite3_free()]. ^Both routines return a** NULL pointer if [sqlite3_malloc()] is unable to allocate enough** memory to hold the resulting string.**** ^(The sqlite3_snprintf() routine is similar to "snprintf()" from** the standard C library. The result is written into the** buffer supplied as the second parameter whose size is given by** the first parameter. Note that the order of the** first two parameters is reversed from snprintf().)^ This is an** historical accident that cannot be fixed without breaking** backwards compatibility. ^(Note also that sqlite3_snprintf()** returns a pointer to its buffer instead of the number of** characters actually written into the buffer.)^ We admit that** the number of characters written would be a more useful return** value but we cannot change the implementation of sqlite3_snprintf()** now without breaking compatibility.**** ^As long as the buffer size is greater than zero, sqlite3_snprintf()** guarantees that the buffer is always zero-terminated. ^The first** parameter "n" is the total size of the buffer, including space for** the zero terminator. So the longest string that can be completely** written will be n-1 characters.**** ^The sqlite3_vsnprintf() routine is a varargs version of sqlite3_snprintf().**** These routines all implement some additional formatting** options that are useful for constructing SQL statements.** All of the usual printf() formatting options apply. In addition, there** is are "%q", "%Q", "%w" and "%z" options.**** ^(The %q option works like %s in that it substitutes a nul-terminated** string from the argument list. But %q also doubles every '\'' character.** %q is designed for use inside a string literal.)^ By doubling each '\''** character it escapes that character and allows it to be inserted into** the string.**** For example, assume the string variable zText contains text as follows:**** <blockquote><pre>** char *zText = "It's a happy day!";** </pre></blockquote>**** One can use this text in an SQL statement as follows:**** <blockquote><pre>** char *zSQL = sqlite3_mprintf("INSERT INTO table VALUES('%q')", zText);** sqlite3_exec(db, zSQL, 0, 0, 0);** sqlite3_free(zSQL);** </pre></blockquote>**** Because the %q format string is used, the '\'' character in zText** is escaped and the SQL generated is as follows:**** <blockquote><pre>** INSERT INTO table1 VALUES('It''s a happy day!')** </pre></blockquote>**** This is correct. Had we used %s instead of %q, the generated SQL** would have looked like this:**** <blockquote><pre>** INSERT INTO table1 VALUES('It's a happy day!');** </pre></blockquote>**** This second example is an SQL syntax error. As a general rule you should** always use %q instead of %s when inserting text into a string literal.**** ^(The %Q option works like %q except it also adds single quotes around** the outside of the total string. Additionally, if the parameter in the** argument list is a NULL pointer, %Q substitutes the text "NULL" (without** single quotes).)^ So, for example, one could say:**** <blockquote><pre>** char *zSQL = sqlite3_mprintf("INSERT INTO table VALUES(%Q)", zText);** sqlite3_exec(db, zSQL, 0, 0, 0);** sqlite3_free(zSQL);** </pre></blockquote>**** The code above will render a correct SQL statement in the zSQL** variable even if the zText variable is a NULL pointer.**** ^(The "%w" formatting option is like "%q" except that it expects to** be contained within double-quotes instead of single quotes, and it** escapes the double-quote character instead of the single-quote** character.)^ The "%w" formatting option is intended for safely inserting** table and column names into a constructed SQL statement.**** ^(The "%z" formatting option works like "%s" but with the** addition that after the string has been read and copied into** the result, [sqlite3_free()] is called on the input string.)^*/SQLITE_APIchar*sqlite3_mprintf(constchar*,...);SQLITE_APIchar*sqlite3_vmprintf(constchar*,va_list);SQLITE_APIchar*sqlite3_snprintf(int,char*,constchar*,...);SQLITE_APIchar*sqlite3_vsnprintf(int,char*,constchar*,va_list);/*** CAPI3REF: Memory Allocation Subsystem**** The SQLite core uses these three routines for all of its own** internal memory allocation needs. "Core" in the previous sentence** does not include operating-system specific VFS implementation. The** Windows VFS uses native malloc() and free() for some operations.**** ^The sqlite3_malloc() routine returns a pointer to a block** of memory at least N bytes in length, where N is the parameter.** ^If sqlite3_malloc() is unable to obtain sufficient free** memory, it returns a NULL pointer. ^If the parameter N to** sqlite3_malloc() is zero or negative then sqlite3_malloc() returns** a NULL pointer.**** ^The sqlite3_malloc64(N) routine works just like** sqlite3_malloc(N) except that N is an unsigned 64-bit integer instead** of a signed 32-bit integer.**** ^Calling sqlite3_free() with a pointer previously returned** by sqlite3_malloc() or sqlite3_realloc() releases that memory so** that it might be reused. ^The sqlite3_free() routine is** a no-op if is called with a NULL pointer. Passing a NULL pointer** to sqlite3_free() is harmless. After being freed, memory** should neither be read nor written. Even reading previously freed** memory might result in a segmentation fault or other severe error.** Memory corruption, a segmentation fault, or other severe error** might result if sqlite3_free() is called with a non-NULL pointer that** was not obtained from sqlite3_malloc() or sqlite3_realloc().**** ^The sqlite3_realloc(X,N) interface attempts to resize a** prior memory allocation X to be at least N bytes.** ^If the X parameter to sqlite3_realloc(X,N)** is a NULL pointer then its behavior is identical to calling** sqlite3_malloc(N).** ^If the N parameter to sqlite3_realloc(X,N) is zero or** negative then the behavior is exactly the same as calling** sqlite3_free(X).** ^sqlite3_realloc(X,N) returns a pointer to a memory allocation** of at least N bytes in size or NULL if insufficient memory is available.** ^If M is the size of the prior allocation, then min(N,M) bytes** of the prior allocation are copied into the beginning of buffer returned** by sqlite3_realloc(X,N) and the prior allocation is freed.** ^If sqlite3_realloc(X,N) returns NULL and N is positive, then the** prior allocation is not freed.**** ^The sqlite3_realloc64(X,N) interfaces works the same as** sqlite3_realloc(X,N) except that N is a 64-bit unsigned integer instead** of a 32-bit signed integer.**** ^If X is a memory allocation previously obtained from sqlite3_malloc(),** sqlite3_malloc64(), sqlite3_realloc(), or sqlite3_realloc64(), then** sqlite3_msize(X) returns the size of that memory allocation in bytes.** ^The value returned by sqlite3_msize(X) might be larger than the number** of bytes requested when X was allocated. ^If X is a NULL pointer then** sqlite3_msize(X) returns zero. If X points to something that is not** the beginning of memory allocation, or if it points to a formerly** valid memory allocation that has now been freed, then the behavior** of sqlite3_msize(X) is undefined and possibly harmful.**** ^The memory returned by sqlite3_malloc(), sqlite3_realloc(),** sqlite3_malloc64(), and sqlite3_realloc64()** is always aligned to at least an 8 byte boundary, or to a** 4 byte boundary if the [SQLITE_4_BYTE_ALIGNED_MALLOC] compile-time** option is used.**** In SQLite version 3.5.0 and 3.5.1, it was possible to define** the SQLITE_OMIT_MEMORY_ALLOCATION which would cause the built-in** implementation of these routines to be omitted. That capability** is no longer provided. Only built-in memory allocators can be used.**** Prior to SQLite version 3.7.10, the Windows OS interface layer called** the system malloc() and free() directly when converting** filenames between the UTF-8 encoding used by SQLite** and whatever filename encoding is used by the particular Windows** installation. Memory allocation errors were detected, but** they were reported back as [SQLITE_CANTOPEN] or** [SQLITE_IOERR] rather than [SQLITE_NOMEM].**** The pointer arguments to [sqlite3_free()] and [sqlite3_realloc()]** must be either NULL or else pointers obtained from a prior** invocation of [sqlite3_malloc()] or [sqlite3_realloc()] that have** not yet been released.**** The application must not read or write any part of** a block of memory after it has been released using** [sqlite3_free()] or [sqlite3_realloc()].*/SQLITE_APIvoid*sqlite3_malloc(int);SQLITE_APIvoid*sqlite3_malloc64(sqlite3_uint64);SQLITE_APIvoid*sqlite3_realloc(void*,int);SQLITE_APIvoid*sqlite3_realloc64(void*,sqlite3_uint64);SQLITE_APIvoidsqlite3_free(void*);SQLITE_APIsqlite3_uint64sqlite3_msize(void*);/*** CAPI3REF: Memory Allocator Statistics**** SQLite provides these two interfaces for reporting on the status** of the [sqlite3_malloc()], [sqlite3_free()], and [sqlite3_realloc()]** routines, which form the built-in memory allocation subsystem.**** ^The [sqlite3_memory_used()] routine returns the number of bytes** of memory currently outstanding (malloced but not freed).** ^The [sqlite3_memory_highwater()] routine returns the maximum** value of [sqlite3_memory_used()] since the high-water mark** was last reset. ^The values returned by [sqlite3_memory_used()] and** [sqlite3_memory_highwater()] include any overhead** added by SQLite in its implementation of [sqlite3_malloc()],** but not overhead added by the any underlying system library** routines that [sqlite3_malloc()] may call.**** ^The memory high-water mark is reset to the current value of** [sqlite3_memory_used()] if and only if the parameter to** [sqlite3_memory_highwater()] is true. ^The value returned** by [sqlite3_memory_highwater(1)] is the high-water mark** prior to the reset.*/SQLITE_APIsqlite3_int64sqlite3_memory_used(void);SQLITE_APIsqlite3_int64sqlite3_memory_highwater(intresetFlag);/*** CAPI3REF: Pseudo-Random Number Generator**** SQLite contains a high-quality pseudo-random number generator (PRNG) used to** select random [ROWID | ROWIDs] when inserting new records into a table that** already uses the largest possible [ROWID]. The PRNG is also used for** the build-in random() and randomblob() SQL functions. This interface allows** applications to access the same PRNG for other purposes.**** ^A call to this routine stores N bytes of randomness into buffer P.** ^The P parameter can be a NULL pointer.**** ^If this routine has not been previously called or if the previous** call had N less than one or a NULL pointer for P, then the PRNG is** seeded using randomness obtained from the xRandomness method of** the default [sqlite3_vfs] object.** ^If the previous call to this routine had an N of 1 or more and a** non-NULL P then the pseudo-randomness is generated** internally and without recourse to the [sqlite3_vfs] xRandomness** method.*/SQLITE_APIvoidsqlite3_randomness(intN,void*P);/*** CAPI3REF: Compile-Time Authorization Callbacks** METHOD: sqlite3**** ^This routine registers an authorizer callback with a particular** [database connection], supplied in the first argument.** ^The authorizer callback is invoked as SQL statements are being compiled** by [sqlite3_prepare()] or its variants [sqlite3_prepare_v2()],** [sqlite3_prepare16()] and [sqlite3_prepare16_v2()]. ^At various** points during the compilation process, as logic is being created** to perform various actions, the authorizer callback is invoked to** see if those actions are allowed. ^The authorizer callback should** return [SQLITE_OK] to allow the action, [SQLITE_IGNORE] to disallow the** specific action but allow the SQL statement to continue to be** compiled, or [SQLITE_DENY] to cause the entire SQL statement to be** rejected with an error. ^If the authorizer callback returns** any value other than [SQLITE_IGNORE], [SQLITE_OK], or [SQLITE_DENY]** then the [sqlite3_prepare_v2()] or equivalent call that triggered** the authorizer will fail with an error message.**** When the callback returns [SQLITE_OK], that means the operation** requested is ok. ^When the callback returns [SQLITE_DENY], the** [sqlite3_prepare_v2()] or equivalent call that triggered the** authorizer will fail with an error message explaining that** access is denied. **** ^The first parameter to the authorizer callback is a copy of the third** parameter to the sqlite3_set_authorizer() interface. ^The second parameter** to the callback is an integer [SQLITE_COPY | action code] that specifies** the particular action to be authorized. ^The third through sixth parameters** to the callback are zero-terminated strings that contain additional** details about the action to be authorized.**** ^If the action code is [SQLITE_READ]** and the callback returns [SQLITE_IGNORE] then the** [prepared statement] statement is constructed to substitute** a NULL value in place of the table column that would have** been read if [SQLITE_OK] had been returned. The [SQLITE_IGNORE]** return can be used to deny an untrusted user access to individual** columns of a table.** ^If the action code is [SQLITE_DELETE] and the callback returns** [SQLITE_IGNORE] then the [DELETE] operation proceeds but the** [truncate optimization] is disabled and all rows are deleted individually.**** An authorizer is used when [sqlite3_prepare | preparing]** SQL statements from an untrusted source, to ensure that the SQL statements** do not try to access data they are not allowed to see, or that they do not** try to execute malicious statements that damage the database. For** example, an application may allow a user to enter arbitrary** SQL queries for evaluation by a database. But the application does** not want the user to be able to make arbitrary changes to the** database. An authorizer could then be put in place while the** user-entered SQL is being [sqlite3_prepare | prepared] that** disallows everything except [SELECT] statements.**** Applications that need to process SQL from untrusted sources** might also consider lowering resource limits using [sqlite3_limit()]** and limiting database size using the [max_page_count] [PRAGMA]** in addition to using an authorizer.**** ^(Only a single authorizer can be in place on a database connection** at a time. Each call to sqlite3_set_authorizer overrides the** previous call.)^ ^Disable the authorizer by installing a NULL callback.** The authorizer is disabled by default.**** The authorizer callback must not do anything that will modify** the database connection that invoked the authorizer callback.** Note that [sqlite3_prepare_v2()] and [sqlite3_step()] both modify their** database connections for the meaning of "modify" in this paragraph.**** ^When [sqlite3_prepare_v2()] is used to prepare a statement, the** statement might be re-prepared during [sqlite3_step()] due to a ** schema change. Hence, the application should ensure that the** correct authorizer callback remains in place during the [sqlite3_step()].**** ^Note that the authorizer callback is invoked only during** [sqlite3_prepare()] or its variants. Authorization is not** performed during statement evaluation in [sqlite3_step()], unless** as stated in the previous paragraph, sqlite3_step() invokes** sqlite3_prepare_v2() to reprepare a statement after a schema change.*/SQLITE_APIintsqlite3_set_authorizer(sqlite3*,int(*xAuth)(void*,int,constchar*,constchar*,constchar*,constchar*),void*pUserData);/*** CAPI3REF: Authorizer Return Codes**** The [sqlite3_set_authorizer | authorizer callback function] must** return either [SQLITE_OK] or one of these two constants in order** to signal SQLite whether or not the action is permitted. See the** [sqlite3_set_authorizer | authorizer documentation] for additional** information.**** Note that SQLITE_IGNORE is also used as a [conflict resolution mode]** returned from the [sqlite3_vtab_on_conflict()] interface.*/#define SQLITE_DENY 1 /* Abort the SQL statement with an error */#define SQLITE_IGNORE 2 /* Don't allow access, but don't generate an error *//*** CAPI3REF: Authorizer Action Codes**** The [sqlite3_set_authorizer()] interface registers a callback function** that is invoked to authorize certain SQL statement actions. The** second parameter to the callback is an integer code that specifies** what action is being authorized. These are the integer action codes that** the authorizer callback may be passed.**** These action code values signify what kind of operation is to be** authorized. The 3rd and 4th parameters to the authorization** callback function will be parameters or NULL depending on which of these** codes is used as the second parameter. ^(The 5th parameter to the** authorizer callback is the name of the database ("main", "temp",** etc.) if applicable.)^ ^The 6th parameter to the authorizer callback** is the name of the inner-most trigger or view that is responsible for** the access attempt or NULL if this access attempt is directly from** top-level SQL code.*//******************************************* 3rd ************ 4th ***********/#define SQLITE_CREATE_INDEX 1 /* Index Name Table Name */#define SQLITE_CREATE_TABLE 2 /* Table Name NULL */#define SQLITE_CREATE_TEMP_INDEX 3 /* Index Name Table Name */#define SQLITE_CREATE_TEMP_TABLE 4 /* Table Name NULL */#define SQLITE_CREATE_TEMP_TRIGGER 5 /* Trigger Name Table Name */#define SQLITE_CREATE_TEMP_VIEW 6 /* View Name NULL */#define SQLITE_CREATE_TRIGGER 7 /* Trigger Name Table Name */#define SQLITE_CREATE_VIEW 8 /* View Name NULL */#define SQLITE_DELETE 9 /* Table Name NULL */#define SQLITE_DROP_INDEX 10 /* Index Name Table Name */#define SQLITE_DROP_TABLE 11 /* Table Name NULL */#define SQLITE_DROP_TEMP_INDEX 12 /* Index Name Table Name */#define SQLITE_DROP_TEMP_TABLE 13 /* Table Name NULL */#define SQLITE_DROP_TEMP_TRIGGER 14 /* Trigger Name Table Name */#define SQLITE_DROP_TEMP_VIEW 15 /* View Name NULL */#define SQLITE_DROP_TRIGGER 16 /* Trigger Name Table Name */#define SQLITE_DROP_VIEW 17 /* View Name NULL */#define SQLITE_INSERT 18 /* Table Name NULL */#define SQLITE_PRAGMA 19 /* Pragma Name 1st arg or NULL */#define SQLITE_READ 20 /* Table Name Column Name */#define SQLITE_SELECT 21 /* NULL NULL */#define SQLITE_TRANSACTION 22 /* Operation NULL */#define SQLITE_UPDATE 23 /* Table Name Column Name */#define SQLITE_ATTACH 24 /* Filename NULL */#define SQLITE_DETACH 25 /* Database Name NULL */#define SQLITE_ALTER_TABLE 26 /* Database Name Table Name */#define SQLITE_REINDEX 27 /* Index Name NULL */#define SQLITE_ANALYZE 28 /* Table Name NULL */#define SQLITE_CREATE_VTABLE 29 /* Table Name Module Name */#define SQLITE_DROP_VTABLE 30 /* Table Name Module Name */#define SQLITE_FUNCTION 31 /* NULL Function Name */#define SQLITE_SAVEPOINT 32 /* Operation Savepoint Name */#define SQLITE_COPY 0 /* No longer used */#define SQLITE_RECURSIVE 33 /* NULL NULL *//*** CAPI3REF: Tracing And Profiling Functions** METHOD: sqlite3**** These routines are deprecated. Use the [sqlite3_trace_v2()] interface** instead of the routines described here.**** These routines register callback functions that can be used for** tracing and profiling the execution of SQL statements.**** ^The callback function registered by sqlite3_trace() is invoked at** various times when an SQL statement is being run by [sqlite3_step()].** ^The sqlite3_trace() callback is invoked with a UTF-8 rendering of the** SQL statement text as the statement first begins executing.** ^(Additional sqlite3_trace() callbacks might occur** as each triggered subprogram is entered. The callbacks for triggers** contain a UTF-8 SQL comment that identifies the trigger.)^**** The [SQLITE_TRACE_SIZE_LIMIT] compile-time option can be used to limit** the length of [bound parameter] expansion in the output of sqlite3_trace().**** ^The callback function registered by sqlite3_profile() is invoked** as each SQL statement finishes. ^The profile callback contains** the original statement text and an estimate of wall-clock time** of how long that statement took to run. ^The profile callback** time is in units of nanoseconds, however the current implementation** is only capable of millisecond resolution so the six least significant** digits in the time are meaningless. Future versions of SQLite** might provide greater resolution on the profiler callback. The** sqlite3_profile() function is considered experimental and is** subject to change in future versions of SQLite.*/SQLITE_APISQLITE_DEPRECATEDvoid*sqlite3_trace(sqlite3*,void(*xTrace)(void*,constchar*),void*);SQLITE_APISQLITE_DEPRECATEDvoid*sqlite3_profile(sqlite3*,void(*xProfile)(void*,constchar*,sqlite3_uint64),void*);/*** CAPI3REF: SQL Trace Event Codes** KEYWORDS: SQLITE_TRACE**** These constants identify classes of events that can be monitored** using the [sqlite3_trace_v2()] tracing logic. The third argument** to [sqlite3_trace_v2()] is an OR-ed combination of one or more of** the following constants. ^The first argument to the trace callback** is one of the following constants.**** New tracing constants may be added in future releases.**** ^A trace callback has four arguments: xCallback(T,C,P,X).** ^The T argument is one of the integer type codes above.** ^The C argument is a copy of the context pointer passed in as the** fourth argument to [sqlite3_trace_v2()].** The P and X arguments are pointers whose meanings depend on T.**** <dl>** [[SQLITE_TRACE_STMT]] <dt>SQLITE_TRACE_STMT</dt>** <dd>^An SQLITE_TRACE_STMT callback is invoked when a prepared statement** first begins running and possibly at other times during the** execution of the prepared statement, such as at the start of each** trigger subprogram. ^The P argument is a pointer to the** [prepared statement]. ^The X argument is a pointer to a string which** is the unexpanded SQL text of the prepared statement or an SQL comment ** that indicates the invocation of a trigger. ^The callback can compute** the same text that would have been returned by the legacy [sqlite3_trace()]** interface by using the X argument when X begins with "--" and invoking** [sqlite3_expanded_sql(P)] otherwise.**** [[SQLITE_TRACE_PROFILE]] <dt>SQLITE_TRACE_PROFILE</dt>** <dd>^An SQLITE_TRACE_PROFILE callback provides approximately the same** information as is provided by the [sqlite3_profile()] callback.** ^The P argument is a pointer to the [prepared statement] and the** X argument points to a 64-bit integer which is the estimated of** the number of nanosecond that the prepared statement took to run.** ^The SQLITE_TRACE_PROFILE callback is invoked when the statement finishes.**** [[SQLITE_TRACE_ROW]] <dt>SQLITE_TRACE_ROW</dt>** <dd>^An SQLITE_TRACE_ROW callback is invoked whenever a prepared** statement generates a single row of result. ** ^The P argument is a pointer to the [prepared statement] and the** X argument is unused.**** [[SQLITE_TRACE_CLOSE]] <dt>SQLITE_TRACE_CLOSE</dt>** <dd>^An SQLITE_TRACE_CLOSE callback is invoked when a database** connection closes.** ^The P argument is a pointer to the [database connection] object** and the X argument is unused.** </dl>*/#define SQLITE_TRACE_STMT 0x01#define SQLITE_TRACE_PROFILE 0x02#define SQLITE_TRACE_ROW 0x04#define SQLITE_TRACE_CLOSE 0x08/*** CAPI3REF: SQL Trace Hook** METHOD: sqlite3**** ^The sqlite3_trace_v2(D,M,X,P) interface registers a trace callback** function X against [database connection] D, using property mask M** and context pointer P. ^If the X callback is** NULL or if the M mask is zero, then tracing is disabled. The** M argument should be the bitwise OR-ed combination of** zero or more [SQLITE_TRACE] constants.**** ^Each call to either sqlite3_trace() or sqlite3_trace_v2() overrides ** (cancels) any prior calls to sqlite3_trace() or sqlite3_trace_v2().**** ^The X callback is invoked whenever any of the events identified by ** mask M occur. ^The integer return value from the callback is currently** ignored, though this may change in future releases. Callback** implementations should return zero to ensure future compatibility.**** ^A trace callback is invoked with four arguments: callback(T,C,P,X).** ^The T argument is one of the [SQLITE_TRACE]** constants to indicate why the callback was invoked.** ^The C argument is a copy of the context pointer.** The P and X arguments are pointers whose meanings depend on T.**** The sqlite3_trace_v2() interface is intended to replace the legacy** interfaces [sqlite3_trace()] and [sqlite3_profile()], both of which** are deprecated.*/SQLITE_APIintsqlite3_trace_v2(sqlite3*,unsigneduMask,int(*xCallback)(unsigned,void*,void*,void*),void*pCtx);/*** CAPI3REF: Query Progress Callbacks** METHOD: sqlite3**** ^The sqlite3_progress_handler(D,N,X,P) interface causes the callback** function X to be invoked periodically during long running calls to** [sqlite3_exec()], [sqlite3_step()] and [sqlite3_get_table()] for** database connection D. An example use for this** interface is to keep a GUI updated during a large query.**** ^The parameter P is passed through as the only parameter to the ** callback function X. ^The parameter N is the approximate number of ** [virtual machine instructions] that are evaluated between successive** invocations of the callback X. ^If N is less than one then the progress** handler is disabled.**** ^Only a single progress handler may be defined at one time per** [database connection]; setting a new progress handler cancels the** old one. ^Setting parameter X to NULL disables the progress handler.** ^The progress handler is also disabled by setting N to a value less** than 1.**** ^If the progress callback returns non-zero, the operation is** interrupted. This feature can be used to implement a** "Cancel" button on a GUI progress dialog box.**** The progress handler callback must not do anything that will modify** the database connection that invoked the progress handler.** Note that [sqlite3_prepare_v2()] and [sqlite3_step()] both modify their** database connections for the meaning of "modify" in this paragraph.***/SQLITE_APIvoidsqlite3_progress_handler(sqlite3*,int,int(*)(void*),void*);/*** CAPI3REF: Opening A New Database Connection** CONSTRUCTOR: sqlite3**** ^These routines open an SQLite database file as specified by the ** filename argument. ^The filename argument is interpreted as UTF-8 for** sqlite3_open() and sqlite3_open_v2() and as UTF-16 in the native byte** order for sqlite3_open16(). ^(A [database connection] handle is usually** returned in *ppDb, even if an error occurs. The only exception is that** if SQLite is unable to allocate memory to hold the [sqlite3] object,** a NULL will be written into *ppDb instead of a pointer to the [sqlite3]** object.)^ ^(If the database is opened (and/or created) successfully, then** [SQLITE_OK] is returned. Otherwise an [error code] is returned.)^ ^The** [sqlite3_errmsg()] or [sqlite3_errmsg16()] routines can be used to obtain** an English language description of the error following a failure of any** of the sqlite3_open() routines.**** ^The default encoding will be UTF-8 for databases created using** sqlite3_open() or sqlite3_open_v2(). ^The default encoding for databases** created using sqlite3_open16() will be UTF-16 in the native byte order.**** Whether or not an error occurs when it is opened, resources** associated with the [database connection] handle should be released by** passing it to [sqlite3_close()] when it is no longer required.**** The sqlite3_open_v2() interface works like sqlite3_open()** except that it accepts two additional parameters for additional control** over the new database connection. ^(The flags parameter to** sqlite3_open_v2() can take one of** the following three values, optionally combined with the ** [SQLITE_OPEN_NOMUTEX], [SQLITE_OPEN_FULLMUTEX], [SQLITE_OPEN_SHAREDCACHE],** [SQLITE_OPEN_PRIVATECACHE], and/or [SQLITE_OPEN_URI] flags:)^**** <dl>** ^(<dt>[SQLITE_OPEN_READONLY]</dt>** <dd>The database is opened in read-only mode. If the database does not** already exist, an error is returned.</dd>)^**** ^(<dt>[SQLITE_OPEN_READWRITE]</dt>** <dd>The database is opened for reading and writing if possible, or reading** only if the file is write protected by the operating system. In either** case the database must already exist, otherwise an error is returned.</dd>)^**** ^(<dt>[SQLITE_OPEN_READWRITE] | [SQLITE_OPEN_CREATE]</dt>** <dd>The database is opened for reading and writing, and is created if** it does not already exist. This is the behavior that is always used for** sqlite3_open() and sqlite3_open16().</dd>)^** </dl>**** If the 3rd parameter to sqlite3_open_v2() is not one of the** combinations shown above optionally combined with other** [SQLITE_OPEN_READONLY | SQLITE_OPEN_* bits]** then the behavior is undefined.**** ^If the [SQLITE_OPEN_NOMUTEX] flag is set, then the database connection** opens in the multi-thread [threading mode] as long as the single-thread** mode has not been set at compile-time or start-time. ^If the** [SQLITE_OPEN_FULLMUTEX] flag is set then the database connection opens** in the serialized [threading mode] unless single-thread was** previously selected at compile-time or start-time.** ^The [SQLITE_OPEN_SHAREDCACHE] flag causes the database connection to be** eligible to use [shared cache mode], regardless of whether or not shared** cache is enabled using [sqlite3_enable_shared_cache()]. ^The** [SQLITE_OPEN_PRIVATECACHE] flag causes the database connection to not** participate in [shared cache mode] even if it is enabled.**** ^The fourth parameter to sqlite3_open_v2() is the name of the** [sqlite3_vfs] object that defines the operating system interface that** the new database connection should use. ^If the fourth parameter is** a NULL pointer then the default [sqlite3_vfs] object is used.**** ^If the filename is ":memory:", then a private, temporary in-memory database** is created for the connection. ^This in-memory database will vanish when** the database connection is closed. Future versions of SQLite might** make use of additional special filenames that begin with the ":" character.** It is recommended that when a database filename actually does begin with** a ":" character you should prefix the filename with a pathname such as** "./" to avoid ambiguity.**** ^If the filename is an empty string, then a private, temporary** on-disk database will be created. ^This private database will be** automatically deleted as soon as the database connection is closed.**** [[URI filenames in sqlite3_open()]] <h3>URI Filenames</h3>**** ^If [URI filename] interpretation is enabled, and the filename argument** begins with "file:", then the filename is interpreted as a URI. ^URI** filename interpretation is enabled if the [SQLITE_OPEN_URI] flag is** set in the fourth argument to sqlite3_open_v2(), or if it has** been enabled globally using the [SQLITE_CONFIG_URI] option with the** [sqlite3_config()] method or by the [SQLITE_USE_URI] compile-time option.** As of SQLite version 3.7.7, URI filename interpretation is turned off** by default, but future releases of SQLite might enable URI filename** interpretation by default. See "[URI filenames]" for additional** information.**** URI filenames are parsed according to RFC 3986. ^If the URI contains an** authority, then it must be either an empty string or the string ** "localhost". ^If the authority is not an empty string or "localhost", an ** error is returned to the caller. ^The fragment component of a URI, if ** present, is ignored.**** ^SQLite uses the path component of the URI as the name of the disk file** which contains the database. ^If the path begins with a '/' character, ** then it is interpreted as an absolute path. ^If the path does not begin ** with a '/' (meaning that the authority section is omitted from the URI)** then the path is interpreted as a relative path. ** ^(On windows, the first component of an absolute path ** is a drive specification (e.g. "C:").)^**** [[core URI query parameters]]** The query component of a URI may contain parameters that are interpreted** either by SQLite itself, or by a [VFS | custom VFS implementation].** SQLite and its built-in [VFSes] interpret the** following query parameters:**** <ul>** <li> <b>vfs</b>: ^The "vfs" parameter may be used to specify the name of** a VFS object that provides the operating system interface that should** be used to access the database file on disk. ^If this option is set to** an empty string the default VFS object is used. ^Specifying an unknown** VFS is an error. ^If sqlite3_open_v2() is used and the vfs option is** present, then the VFS specified by the option takes precedence over** the value passed as the fourth parameter to sqlite3_open_v2().**** <li> <b>mode</b>: ^(The mode parameter may be set to either "ro", "rw",** "rwc", or "memory". Attempting to set it to any other value is** an error)^. ** ^If "ro" is specified, then the database is opened for read-only ** access, just as if the [SQLITE_OPEN_READONLY] flag had been set in the ** third argument to sqlite3_open_v2(). ^If the mode option is set to ** "rw", then the database is opened for read-write (but not create) ** access, as if SQLITE_OPEN_READWRITE (but not SQLITE_OPEN_CREATE) had ** been set. ^Value "rwc" is equivalent to setting both ** SQLITE_OPEN_READWRITE and SQLITE_OPEN_CREATE. ^If the mode option is** set to "memory" then a pure [in-memory database] that never reads** or writes from disk is used. ^It is an error to specify a value for** the mode parameter that is less restrictive than that specified by** the flags passed in the third parameter to sqlite3_open_v2().**** <li> <b>cache</b>: ^The cache parameter may be set to either "shared" or** "private". ^Setting it to "shared" is equivalent to setting the** SQLITE_OPEN_SHAREDCACHE bit in the flags argument passed to** sqlite3_open_v2(). ^Setting the cache parameter to "private" is ** equivalent to setting the SQLITE_OPEN_PRIVATECACHE bit.** ^If sqlite3_open_v2() is used and the "cache" parameter is present in** a URI filename, its value overrides any behavior requested by setting** SQLITE_OPEN_PRIVATECACHE or SQLITE_OPEN_SHAREDCACHE flag.**** <li> <b>psow</b>: ^The psow parameter indicates whether or not the** [powersafe overwrite] property does or does not apply to the** storage media on which the database file resides.**** <li> <b>nolock</b>: ^The nolock parameter is a boolean query parameter** which if set disables file locking in rollback journal modes. This** is useful for accessing a database on a filesystem that does not** support locking. Caution: Database corruption might result if two** or more processes write to the same database and any one of those** processes uses nolock=1.**** <li> <b>immutable</b>: ^The immutable parameter is a boolean query** parameter that indicates that the database file is stored on** read-only media. ^When immutable is set, SQLite assumes that the** database file cannot be changed, even by a process with higher** privilege, and so the database is opened read-only and all locking** and change detection is disabled. Caution: Setting the immutable** property on a database file that does in fact change can result** in incorrect query results and/or [SQLITE_CORRUPT] errors.** See also: [SQLITE_IOCAP_IMMUTABLE].** ** </ul>**** ^Specifying an unknown parameter in the query component of a URI is not an** error. Future versions of SQLite might understand additional query** parameters. See "[query parameters with special meaning to SQLite]" for** additional information.**** [[URI filename examples]] <h3>URI filename examples</h3>**** <table border="1" align=center cellpadding=5>** <tr><th> URI filenames <th> Results** <tr><td> file:data.db <td> ** Open the file "data.db" in the current directory.** <tr><td> file:/home/fred/data.db<br>** file:///home/fred/data.db <br> ** file://localhost/home/fred/data.db <br> <td> ** Open the database file "/home/fred/data.db".** <tr><td> file://darkstar/home/fred/data.db <td> ** An error. "darkstar" is not a recognized authority.** <tr><td style="white-space:nowrap"> ** file:///C:/Documents%20and%20Settings/fred/Desktop/data.db** <td> Windows only: Open the file "data.db" on fred's desktop on drive** C:. Note that the %20 escaping in this example is not strictly ** necessary - space characters can be used literally** in URI filenames.** <tr><td> file:data.db?mode=ro&cache=private <td> ** Open file "data.db" in the current directory for read-only access.** Regardless of whether or not shared-cache mode is enabled by** default, use a private cache.** <tr><td> file:/home/fred/data.db?vfs=unix-dotfile <td>** Open file "/home/fred/data.db". Use the special VFS "unix-dotfile"** that uses dot-files in place of posix advisory locking.** <tr><td> file:data.db?mode=readonly <td> ** An error. "readonly" is not a valid option for the "mode" parameter.** </table>**** ^URI hexadecimal escape sequences (%HH) are supported within the path and** query components of a URI. A hexadecimal escape sequence consists of a** percent sign - "%" - followed by exactly two hexadecimal digits ** specifying an octet value. ^Before the path or query components of a** URI filename are interpreted, they are encoded using UTF-8 and all ** hexadecimal escape sequences replaced by a single byte containing the** corresponding octet. If this process generates an invalid UTF-8 encoding,** the results are undefined.**** <b>Note to Windows users:</b> The encoding used for the filename argument** of sqlite3_open() and sqlite3_open_v2() must be UTF-8, not whatever** codepage is currently defined. Filenames containing international** characters must be converted to UTF-8 prior to passing them into** sqlite3_open() or sqlite3_open_v2().**** <b>Note to Windows Runtime users:</b> The temporary directory must be set** prior to calling sqlite3_open() or sqlite3_open_v2(). Otherwise, various** features that require the use of temporary files may fail.**** See also: [sqlite3_temp_directory]*/SQLITE_APIintsqlite3_open(constchar*filename,/* Database filename (UTF-8) */sqlite3**ppDb/* OUT: SQLite db handle */);SQLITE_APIintsqlite3_open16(constvoid*filename,/* Database filename (UTF-16) */sqlite3**ppDb/* OUT: SQLite db handle */);SQLITE_APIintsqlite3_open_v2(constchar*filename,/* Database filename (UTF-8) */sqlite3**ppDb,/* OUT: SQLite db handle */intflags,/* Flags */constchar*zVfs/* Name of VFS module to use */);/*** CAPI3REF: Obtain Values For URI Parameters**** These are utility routines, useful to VFS implementations, that check** to see if a database file was a URI that contained a specific query ** parameter, and if so obtains the value of that query parameter.**** If F is the database filename pointer passed into the xOpen() method of ** a VFS implementation when the flags parameter to xOpen() has one or ** more of the [SQLITE_OPEN_URI] or [SQLITE_OPEN_MAIN_DB] bits set and** P is the name of the query parameter, then** sqlite3_uri_parameter(F,P) returns the value of the P** parameter if it exists or a NULL pointer if P does not appear as a ** query parameter on F. If P is a query parameter of F** has no explicit value, then sqlite3_uri_parameter(F,P) returns** a pointer to an empty string.**** The sqlite3_uri_boolean(F,P,B) routine assumes that P is a boolean** parameter and returns true (1) or false (0) according to the value** of P. The sqlite3_uri_boolean(F,P,B) routine returns true (1) if the** value of query parameter P is one of "yes", "true", or "on" in any** case or if the value begins with a non-zero number. The ** sqlite3_uri_boolean(F,P,B) routines returns false (0) if the value of** query parameter P is one of "no", "false", or "off" in any case or** if the value begins with a numeric zero. If P is not a query** parameter on F or if the value of P is does not match any of the** above, then sqlite3_uri_boolean(F,P,B) returns (B!=0).**** The sqlite3_uri_int64(F,P,D) routine converts the value of P into a** 64-bit signed integer and returns that integer, or D if P does not** exist. If the value of P is something other than an integer, then** zero is returned.** ** If F is a NULL pointer, then sqlite3_uri_parameter(F,P) returns NULL and** sqlite3_uri_boolean(F,P,B) returns B. If F is not a NULL pointer and** is not a database file pathname pointer that SQLite passed into the xOpen** VFS method, then the behavior of this routine is undefined and probably** undesirable.*/SQLITE_APIconstchar*sqlite3_uri_parameter(constchar*zFilename,constchar*zParam);SQLITE_APIintsqlite3_uri_boolean(constchar*zFile,constchar*zParam,intbDefault);SQLITE_APIsqlite3_int64sqlite3_uri_int64(constchar*,constchar*,sqlite3_int64);/*** CAPI3REF: Error Codes And Messages** METHOD: sqlite3**** ^If the most recent sqlite3_* API call associated with ** [database connection] D failed, then the sqlite3_errcode(D) interface** returns the numeric [result code] or [extended result code] for that** API call.** If the most recent API call was successful,** then the return value from sqlite3_errcode() is undefined.** ^The sqlite3_extended_errcode()** interface is the same except that it always returns the ** [extended result code] even when extended result codes are** disabled.**** ^The sqlite3_errmsg() and sqlite3_errmsg16() return English-language** text that describes the error, as either UTF-8 or UTF-16 respectively.** ^(Memory to hold the error message string is managed internally.** The application does not need to worry about freeing the result.** However, the error string might be overwritten or deallocated by** subsequent calls to other SQLite interface functions.)^**** ^The sqlite3_errstr() interface returns the English-language text** that describes the [result code], as UTF-8.** ^(Memory to hold the error message string is managed internally** and must not be freed by the application)^.**** When the serialized [threading mode] is in use, it might be the** case that a second error occurs on a separate thread in between** the time of the first error and the call to these interfaces.** When that happens, the second error will be reported since these** interfaces always report the most recent result. To avoid** this, each thread can obtain exclusive use of the [database connection] D** by invoking [sqlite3_mutex_enter]([sqlite3_db_mutex](D)) before beginning** to use D and invoking [sqlite3_mutex_leave]([sqlite3_db_mutex](D)) after** all calls to the interfaces listed here are completed.**** If an interface fails with SQLITE_MISUSE, that means the interface** was invoked incorrectly by the application. In that case, the** error code and message may or may not be set.*/SQLITE_APIintsqlite3_errcode(sqlite3*db);SQLITE_APIintsqlite3_extended_errcode(sqlite3*db);SQLITE_APIconstchar*sqlite3_errmsg(sqlite3*);SQLITE_APIconstvoid*sqlite3_errmsg16(sqlite3*);SQLITE_APIconstchar*sqlite3_errstr(int);/*** CAPI3REF: Prepared Statement Object** KEYWORDS: {prepared statement} {prepared statements}**** An instance of this object represents a single SQL statement that** has been compiled into binary form and is ready to be evaluated.**** Think of each SQL statement as a separate computer program. The** original SQL text is source code. A prepared statement object ** is the compiled object code. All SQL must be converted into a** prepared statement before it can be run.**** The life-cycle of a prepared statement object usually goes like this:**** <ol>** <li> Create the prepared statement object using [sqlite3_prepare_v2()].** <li> Bind values to [parameters] using the sqlite3_bind_*()** interfaces.** <li> Run the SQL by calling [sqlite3_step()] one or more times.** <li> Reset the prepared statement using [sqlite3_reset()] then go back** to step 2. Do this zero or more times.** <li> Destroy the object using [sqlite3_finalize()].** </ol>*/typedefstructsqlite3_stmtsqlite3_stmt;/*** CAPI3REF: Run-time Limits** METHOD: sqlite3**** ^(This interface allows the size of various constructs to be limited** on a connection by connection basis. The first parameter is the** [database connection] whose limit is to be set or queried. The** second parameter is one of the [limit categories] that define a** class of constructs to be size limited. The third parameter is the** new limit for that construct.)^**** ^If the new limit is a negative number, the limit is unchanged.** ^(For each limit category SQLITE_LIMIT_<i>NAME</i> there is a ** [limits | hard upper bound]** set at compile-time by a C preprocessor macro called** [limits | SQLITE_MAX_<i>NAME</i>].** (The "_LIMIT_" in the name is changed to "_MAX_".))^** ^Attempts to increase a limit above its hard upper bound are** silently truncated to the hard upper bound.**** ^Regardless of whether or not the limit was changed, the ** [sqlite3_limit()] interface returns the prior value of the limit.** ^Hence, to find the current value of a limit without changing it,** simply invoke this interface with the third parameter set to -1.**** Run-time limits are intended for use in applications that manage** both their own internal database and also databases that are controlled** by untrusted external sources. An example application might be a** web browser that has its own databases for storing history and** separate databases controlled by JavaScript applications downloaded** off the Internet. The internal databases can be given the** large, default limits. Databases managed by external sources can** be given much smaller limits designed to prevent a denial of service** attack. Developers might also want to use the [sqlite3_set_authorizer()]** interface to further control untrusted SQL. The size of the database** created by an untrusted script can be contained using the** [max_page_count] [PRAGMA].**** New run-time limit categories may be added in future releases.*/SQLITE_APIintsqlite3_limit(sqlite3*,intid,intnewVal);/*** CAPI3REF: Run-Time Limit Categories** KEYWORDS: {limit category} {*limit categories}**** These constants define various performance limits** that can be lowered at run-time using [sqlite3_limit()].** The synopsis of the meanings of the various limits is shown below.** Additional information is available at [limits | Limits in SQLite].**** <dl>** [[SQLITE_LIMIT_LENGTH]] ^(<dt>SQLITE_LIMIT_LENGTH</dt>** <dd>The maximum size of any string or BLOB or table row, in bytes.<dd>)^**** [[SQLITE_LIMIT_SQL_LENGTH]] ^(<dt>SQLITE_LIMIT_SQL_LENGTH</dt>** <dd>The maximum length of an SQL statement, in bytes.</dd>)^**** [[SQLITE_LIMIT_COLUMN]] ^(<dt>SQLITE_LIMIT_COLUMN</dt>** <dd>The maximum number of columns in a table definition or in the** result set of a [SELECT] or the maximum number of columns in an index** or in an ORDER BY or GROUP BY clause.</dd>)^**** [[SQLITE_LIMIT_EXPR_DEPTH]] ^(<dt>SQLITE_LIMIT_EXPR_DEPTH</dt>** <dd>The maximum depth of the parse tree on any expression.</dd>)^**** [[SQLITE_LIMIT_COMPOUND_SELECT]] ^(<dt>SQLITE_LIMIT_COMPOUND_SELECT</dt>** <dd>The maximum number of terms in a compound SELECT statement.</dd>)^**** [[SQLITE_LIMIT_VDBE_OP]] ^(<dt>SQLITE_LIMIT_VDBE_OP</dt>** <dd>The maximum number of instructions in a virtual machine program** used to implement an SQL statement. This limit is not currently** enforced, though that might be added in some future release of** SQLite.</dd>)^**** [[SQLITE_LIMIT_FUNCTION_ARG]] ^(<dt>SQLITE_LIMIT_FUNCTION_ARG</dt>** <dd>The maximum number of arguments on a function.</dd>)^**** [[SQLITE_LIMIT_ATTACHED]] ^(<dt>SQLITE_LIMIT_ATTACHED</dt>** <dd>The maximum number of [ATTACH | attached databases].)^</dd>**** [[SQLITE_LIMIT_LIKE_PATTERN_LENGTH]]** ^(<dt>SQLITE_LIMIT_LIKE_PATTERN_LENGTH</dt>** <dd>The maximum length of the pattern argument to the [LIKE] or** [GLOB] operators.</dd>)^**** [[SQLITE_LIMIT_VARIABLE_NUMBER]]** ^(<dt>SQLITE_LIMIT_VARIABLE_NUMBER</dt>** <dd>The maximum index number of any [parameter] in an SQL statement.)^**** [[SQLITE_LIMIT_TRIGGER_DEPTH]] ^(<dt>SQLITE_LIMIT_TRIGGER_DEPTH</dt>** <dd>The maximum depth of recursion for triggers.</dd>)^**** [[SQLITE_LIMIT_WORKER_THREADS]] ^(<dt>SQLITE_LIMIT_WORKER_THREADS</dt>** <dd>The maximum number of auxiliary worker threads that a single** [prepared statement] may start.</dd>)^** </dl>*/#define SQLITE_LIMIT_LENGTH 0#define SQLITE_LIMIT_SQL_LENGTH 1#define SQLITE_LIMIT_COLUMN 2#define SQLITE_LIMIT_EXPR_DEPTH 3#define SQLITE_LIMIT_COMPOUND_SELECT 4#define SQLITE_LIMIT_VDBE_OP 5#define SQLITE_LIMIT_FUNCTION_ARG 6#define SQLITE_LIMIT_ATTACHED 7#define SQLITE_LIMIT_LIKE_PATTERN_LENGTH 8#define SQLITE_LIMIT_VARIABLE_NUMBER 9#define SQLITE_LIMIT_TRIGGER_DEPTH 10#define SQLITE_LIMIT_WORKER_THREADS 11/*** CAPI3REF: Compiling An SQL Statement** KEYWORDS: {SQL statement compiler}** METHOD: sqlite3** CONSTRUCTOR: sqlite3_stmt**** To execute an SQL query, it must first be compiled into a byte-code** program using one of these routines.**** The first argument, "db", is a [database connection] obtained from a** prior successful call to [sqlite3_open()], [sqlite3_open_v2()] or** [sqlite3_open16()]. The database connection must not have been closed.**** The second argument, "zSql", is the statement to be compiled, encoded** as either UTF-8 or UTF-16. The sqlite3_prepare() and sqlite3_prepare_v2()** interfaces use UTF-8, and sqlite3_prepare16() and sqlite3_prepare16_v2()** use UTF-16.**** ^If the nByte argument is negative, then zSql is read up to the** first zero terminator. ^If nByte is positive, then it is the** number of bytes read from zSql. ^If nByte is zero, then no prepared** statement is generated.** If the caller knows that the supplied string is nul-terminated, then** there is a small performance advantage to passing an nByte parameter that** is the number of bytes in the input string <i>including</i>** the nul-terminator.**** ^If pzTail is not NULL then *pzTail is made to point to the first byte** past the end of the first SQL statement in zSql. These routines only** compile the first statement in zSql, so *pzTail is left pointing to** what remains uncompiled.**** ^*ppStmt is left pointing to a compiled [prepared statement] that can be** executed using [sqlite3_step()]. ^If there is an error, *ppStmt is set** to NULL. ^If the input text contains no SQL (if the input is an empty** string or a comment) then *ppStmt is set to NULL.** The calling procedure is responsible for deleting the compiled** SQL statement using [sqlite3_finalize()] after it has finished with it.** ppStmt may not be NULL.**** ^On success, the sqlite3_prepare() family of routines return [SQLITE_OK];** otherwise an [error code] is returned.**** The sqlite3_prepare_v2() and sqlite3_prepare16_v2() interfaces are** recommended for all new programs. The two older interfaces are retained** for backwards compatibility, but their use is discouraged.** ^In the "v2" interfaces, the prepared statement** that is returned (the [sqlite3_stmt] object) contains a copy of the** original SQL text. This causes the [sqlite3_step()] interface to** behave differently in three ways:**** <ol>** <li>** ^If the database schema changes, instead of returning [SQLITE_SCHEMA] as it** always used to do, [sqlite3_step()] will automatically recompile the SQL** statement and try to run it again. As many as [SQLITE_MAX_SCHEMA_RETRY]** retries will occur before sqlite3_step() gives up and returns an error.** </li>**** <li>** ^When an error occurs, [sqlite3_step()] will return one of the detailed** [error codes] or [extended error codes]. ^The legacy behavior was that** [sqlite3_step()] would only return a generic [SQLITE_ERROR] result code** and the application would have to make a second call to [sqlite3_reset()]** in order to find the underlying cause of the problem. With the "v2" prepare** interfaces, the underlying reason for the error is returned immediately.** </li>**** <li>** ^If the specific value bound to [parameter | host parameter] in the ** WHERE clause might influence the choice of query plan for a statement,** then the statement will be automatically recompiled, as if there had been ** a schema change, on the first [sqlite3_step()] call following any change** to the [sqlite3_bind_text | bindings] of that [parameter]. ** ^The specific value of WHERE-clause [parameter] might influence the ** choice of query plan if the parameter is the left-hand side of a [LIKE]** or [GLOB] operator or if the parameter is compared to an indexed column** and the [SQLITE_ENABLE_STAT3] compile-time option is enabled.** </li>** </ol>*/SQLITE_APIintsqlite3_prepare(sqlite3*db,/* Database handle */constchar*zSql,/* SQL statement, UTF-8 encoded */intnByte,/* Maximum length of zSql in bytes. */sqlite3_stmt**ppStmt,/* OUT: Statement handle */constchar**pzTail/* OUT: Pointer to unused portion of zSql */);SQLITE_APIintsqlite3_prepare_v2(sqlite3*db,/* Database handle */constchar*zSql,/* SQL statement, UTF-8 encoded */intnByte,/* Maximum length of zSql in bytes. */sqlite3_stmt**ppStmt,/* OUT: Statement handle */constchar**pzTail/* OUT: Pointer to unused portion of zSql */);SQLITE_APIintsqlite3_prepare16(sqlite3*db,/* Database handle */constvoid*zSql,/* SQL statement, UTF-16 encoded */intnByte,/* Maximum length of zSql in bytes. */sqlite3_stmt**ppStmt,/* OUT: Statement handle */constvoid**pzTail/* OUT: Pointer to unused portion of zSql */);SQLITE_APIintsqlite3_prepare16_v2(sqlite3*db,/* Database handle */constvoid*zSql,/* SQL statement, UTF-16 encoded */intnByte,/* Maximum length of zSql in bytes. */sqlite3_stmt**ppStmt,/* OUT: Statement handle */constvoid**pzTail/* OUT: Pointer to unused portion of zSql */);/*** CAPI3REF: Retrieving Statement SQL** METHOD: sqlite3_stmt**** ^The sqlite3_sql(P) interface returns a pointer to a copy of the UTF-8** SQL text used to create [prepared statement] P if P was** created by either [sqlite3_prepare_v2()] or [sqlite3_prepare16_v2()].** ^The sqlite3_expanded_sql(P) interface returns a pointer to a UTF-8** string containing the SQL text of prepared statement P with** [bound parameters] expanded.**** ^(For example, if a prepared statement is created using the SQL** text "SELECT $abc,:xyz" and if parameter $abc is bound to integer 2345** and parameter :xyz is unbound, then sqlite3_sql() will return** the original string, "SELECT $abc,:xyz" but sqlite3_expanded_sql()** will return "SELECT 2345,NULL".)^**** ^The sqlite3_expanded_sql() interface returns NULL if insufficient memory** is available to hold the result, or if the result would exceed the** the maximum string length determined by the [SQLITE_LIMIT_LENGTH].**** ^The [SQLITE_TRACE_SIZE_LIMIT] compile-time option limits the size of** bound parameter expansions. ^The [SQLITE_OMIT_TRACE] compile-time** option causes sqlite3_expanded_sql() to always return NULL.**** ^The string returned by sqlite3_sql(P) is managed by SQLite and is** automatically freed when the prepared statement is finalized.** ^The string returned by sqlite3_expanded_sql(P), on the other hand,** is obtained from [sqlite3_malloc()] and must be free by the application** by passing it to [sqlite3_free()].*/SQLITE_APIconstchar*sqlite3_sql(sqlite3_stmt*pStmt);SQLITE_APIchar*sqlite3_expanded_sql(sqlite3_stmt*pStmt);/*** CAPI3REF: Determine If An SQL Statement Writes The Database** METHOD: sqlite3_stmt**** ^The sqlite3_stmt_readonly(X) interface returns true (non-zero) if** and only if the [prepared statement] X makes no direct changes to** the content of the database file.**** Note that [application-defined SQL functions] or** [virtual tables] might change the database indirectly as a side effect. ** ^(For example, if an application defines a function "eval()" that ** calls [sqlite3_exec()], then the following SQL statement would** change the database file through side-effects:**** <blockquote><pre>** SELECT eval('DELETE FROM t1') FROM t2;** </pre></blockquote>**** But because the [SELECT] statement does not change the database file** directly, sqlite3_stmt_readonly() would still return true.)^**** ^Transaction control statements such as [BEGIN], [COMMIT], [ROLLBACK],** [SAVEPOINT], and [RELEASE] cause sqlite3_stmt_readonly() to return true,** since the statements themselves do not actually modify the database but** rather they control the timing of when other statements modify the ** database. ^The [ATTACH] and [DETACH] statements also cause** sqlite3_stmt_readonly() to return true since, while those statements** change the configuration of a database connection, they do not make ** changes to the content of the database files on disk.*/SQLITE_APIintsqlite3_stmt_readonly(sqlite3_stmt*pStmt);/*** CAPI3REF: Determine If A Prepared Statement Has Been Reset** METHOD: sqlite3_stmt**** ^The sqlite3_stmt_busy(S) interface returns true (non-zero) if the** [prepared statement] S has been stepped at least once using ** [sqlite3_step(S)] but has neither run to completion (returned** [SQLITE_DONE] from [sqlite3_step(S)]) nor** been reset using [sqlite3_reset(S)]. ^The sqlite3_stmt_busy(S)** interface returns false if S is a NULL pointer. If S is not a ** NULL pointer and is not a pointer to a valid [prepared statement]** object, then the behavior is undefined and probably undesirable.**** This interface can be used in combination [sqlite3_next_stmt()]** to locate all prepared statements associated with a database ** connection that are in need of being reset. This can be used,** for example, in diagnostic routines to search for prepared ** statements that are holding a transaction open.*/SQLITE_APIintsqlite3_stmt_busy(sqlite3_stmt*);/*** CAPI3REF: Dynamically Typed Value Object** KEYWORDS: {protected sqlite3_value} {unprotected sqlite3_value}**** SQLite uses the sqlite3_value object to represent all values** that can be stored in a database table. SQLite uses dynamic typing** for the values it stores. ^Values stored in sqlite3_value objects** can be integers, floating point values, strings, BLOBs, or NULL.**** An sqlite3_value object may be either "protected" or "unprotected".** Some interfaces require a protected sqlite3_value. Other interfaces** will accept either a protected or an unprotected sqlite3_value.** Every interface that accepts sqlite3_value arguments specifies** whether or not it requires a protected sqlite3_value. The** [sqlite3_value_dup()] interface can be used to construct a new ** protected sqlite3_value from an unprotected sqlite3_value.**** The terms "protected" and "unprotected" refer to whether or not** a mutex is held. An internal mutex is held for a protected** sqlite3_value object but no mutex is held for an unprotected** sqlite3_value object. If SQLite is compiled to be single-threaded** (with [SQLITE_THREADSAFE=0] and with [sqlite3_threadsafe()] returning 0)** or if SQLite is run in one of reduced mutex modes ** [SQLITE_CONFIG_SINGLETHREAD] or [SQLITE_CONFIG_MULTITHREAD]** then there is no distinction between protected and unprotected** sqlite3_value objects and they can be used interchangeably. However,** for maximum code portability it is recommended that applications** still make the distinction between protected and unprotected** sqlite3_value objects even when not strictly required.**** ^The sqlite3_value objects that are passed as parameters into the** implementation of [application-defined SQL functions] are protected.** ^The sqlite3_value object returned by** [sqlite3_column_value()] is unprotected.** Unprotected sqlite3_value objects may only be used with** [sqlite3_result_value()] and [sqlite3_bind_value()].** The [sqlite3_value_blob | sqlite3_value_type()] family of** interfaces require protected sqlite3_value objects.*/typedefstructMemsqlite3_value;/*** CAPI3REF: SQL Function Context Object**** The context in which an SQL function executes is stored in an** sqlite3_context object. ^A pointer to an sqlite3_context object** is always first parameter to [application-defined SQL functions].** The application-defined SQL function implementation will pass this** pointer through into calls to [sqlite3_result_int | sqlite3_result()],** [sqlite3_aggregate_context()], [sqlite3_user_data()],** [sqlite3_context_db_handle()], [sqlite3_get_auxdata()],** and/or [sqlite3_set_auxdata()].*/typedefstructsqlite3_contextsqlite3_context;/*** CAPI3REF: Binding Values To Prepared Statements** KEYWORDS: {host parameter} {host parameters} {host parameter name}** KEYWORDS: {SQL parameter} {SQL parameters} {parameter binding}** METHOD: sqlite3_stmt**** ^(In the SQL statement text input to [sqlite3_prepare_v2()] and its variants,** literals may be replaced by a [parameter] that matches one of following** templates:**** <ul>** <li> ?** <li> ?NNN** <li> :VVV** <li> @VVV** <li> $VVV** </ul>**** In the templates above, NNN represents an integer literal,** and VVV represents an alphanumeric identifier.)^ ^The values of these** parameters (also called "host parameter names" or "SQL parameters")** can be set using the sqlite3_bind_*() routines defined here.**** ^The first argument to the sqlite3_bind_*() routines is always** a pointer to the [sqlite3_stmt] object returned from** [sqlite3_prepare_v2()] or its variants.**** ^The second argument is the index of the SQL parameter to be set.** ^The leftmost SQL parameter has an index of 1. ^When the same named** SQL parameter is used more than once, second and subsequent** occurrences have the same index as the first occurrence.** ^The index for named parameters can be looked up using the** [sqlite3_bind_parameter_index()] API if desired. ^The index** for "?NNN" parameters is the value of NNN.** ^The NNN value must be between 1 and the [sqlite3_limit()]** parameter [SQLITE_LIMIT_VARIABLE_NUMBER] (default value: 999).**** ^The third argument is the value to bind to the parameter.** ^If the third parameter to sqlite3_bind_text() or sqlite3_bind_text16()** or sqlite3_bind_blob() is a NULL pointer then the fourth parameter** is ignored and the end result is the same as sqlite3_bind_null().**** ^(In those routines that have a fourth argument, its value is the** number of bytes in the parameter. To be clear: the value is the** number of <u>bytes</u> in the value, not the number of characters.)^** ^If the fourth parameter to sqlite3_bind_text() or sqlite3_bind_text16()** is negative, then the length of the string is** the number of bytes up to the first zero terminator.** If the fourth parameter to sqlite3_bind_blob() is negative, then** the behavior is undefined.** If a non-negative fourth parameter is provided to sqlite3_bind_text()** or sqlite3_bind_text16() or sqlite3_bind_text64() then** that parameter must be the byte offset** where the NUL terminator would occur assuming the string were NUL** terminated. If any NUL characters occur at byte offsets less than ** the value of the fourth parameter then the resulting string value will** contain embedded NULs. The result of expressions involving strings** with embedded NULs is undefined.**** ^The fifth argument to the BLOB and string binding interfaces** is a destructor used to dispose of the BLOB or** string after SQLite has finished with it. ^The destructor is called** to dispose of the BLOB or string even if the call to bind API fails.** ^If the fifth argument is** the special value [SQLITE_STATIC], then SQLite assumes that the** information is in static, unmanaged space and does not need to be freed.** ^If the fifth argument has the value [SQLITE_TRANSIENT], then** SQLite makes its own private copy of the data immediately, before** the sqlite3_bind_*() routine returns.**** ^The sixth argument to sqlite3_bind_text64() must be one of** [SQLITE_UTF8], [SQLITE_UTF16], [SQLITE_UTF16BE], or [SQLITE_UTF16LE]** to specify the encoding of the text in the third parameter. If** the sixth argument to sqlite3_bind_text64() is not one of the** allowed values shown above, or if the text encoding is different** from the encoding specified by the sixth parameter, then the behavior** is undefined.**** ^The sqlite3_bind_zeroblob() routine binds a BLOB of length N that** is filled with zeroes. ^A zeroblob uses a fixed amount of memory** (just an integer to hold its size) while it is being processed.** Zeroblobs are intended to serve as placeholders for BLOBs whose** content is later written using** [sqlite3_blob_open | incremental BLOB I/O] routines.** ^A negative value for the zeroblob results in a zero-length BLOB.**** ^If any of the sqlite3_bind_*() routines are called with a NULL pointer** for the [prepared statement] or with a prepared statement for which** [sqlite3_step()] has been called more recently than [sqlite3_reset()],** then the call will return [SQLITE_MISUSE]. If any sqlite3_bind_()** routine is passed a [prepared statement] that has been finalized, the** result is undefined and probably harmful.**** ^Bindings are not cleared by the [sqlite3_reset()] routine.** ^Unbound parameters are interpreted as NULL.**** ^The sqlite3_bind_* routines return [SQLITE_OK] on success or an** [error code] if anything goes wrong.** ^[SQLITE_TOOBIG] might be returned if the size of a string or BLOB** exceeds limits imposed by [sqlite3_limit]([SQLITE_LIMIT_LENGTH]) or** [SQLITE_MAX_LENGTH].** ^[SQLITE_RANGE] is returned if the parameter** index is out of range. ^[SQLITE_NOMEM] is returned if malloc() fails.**** See also: [sqlite3_bind_parameter_count()],** [sqlite3_bind_parameter_name()], and [sqlite3_bind_parameter_index()].*/SQLITE_APIintsqlite3_bind_blob(sqlite3_stmt*,int,constvoid*,intn,void(*)(void*));SQLITE_APIintsqlite3_bind_blob64(sqlite3_stmt*,int,constvoid*,sqlite3_uint64,void(*)(void*));SQLITE_APIintsqlite3_bind_double(sqlite3_stmt*,int,double);SQLITE_APIintsqlite3_bind_int(sqlite3_stmt*,int,int);SQLITE_APIintsqlite3_bind_int64(sqlite3_stmt*,int,sqlite3_int64);SQLITE_APIintsqlite3_bind_null(sqlite3_stmt*,int);SQLITE_APIintsqlite3_bind_text(sqlite3_stmt*,int,constchar*,int,void(*)(void*));SQLITE_APIintsqlite3_bind_text16(sqlite3_stmt*,int,constvoid*,int,void(*)(void*));SQLITE_APIintsqlite3_bind_text64(sqlite3_stmt*,int,constchar*,sqlite3_uint64,void(*)(void*),unsignedcharencoding);SQLITE_APIintsqlite3_bind_value(sqlite3_stmt*,int,constsqlite3_value*);SQLITE_APIintsqlite3_bind_zeroblob(sqlite3_stmt*,int,intn);SQLITE_APIintsqlite3_bind_zeroblob64(sqlite3_stmt*,int,sqlite3_uint64);/*** CAPI3REF: Number Of SQL Parameters** METHOD: sqlite3_stmt**** ^This routine can be used to find the number of [SQL parameters]** in a [prepared statement]. SQL parameters are tokens of the** form "?", "?NNN", ":AAA", "$AAA", or "@AAA" that serve as** placeholders for values that are [sqlite3_bind_blob | bound]** to the parameters at a later time.**** ^(This routine actually returns the index of the largest (rightmost)** parameter. For all forms except ?NNN, this will correspond to the** number of unique parameters. If parameters of the ?NNN form are used,** there may be gaps in the list.)^**** See also: [sqlite3_bind_blob|sqlite3_bind()],** [sqlite3_bind_parameter_name()], and** [sqlite3_bind_parameter_index()].*/SQLITE_APIintsqlite3_bind_parameter_count(sqlite3_stmt*);/*** CAPI3REF: Name Of A Host Parameter** METHOD: sqlite3_stmt**** ^The sqlite3_bind_parameter_name(P,N) interface returns** the name of the N-th [SQL parameter] in the [prepared statement] P.** ^(SQL parameters of the form "?NNN" or ":AAA" or "@AAA" or "$AAA"** have a name which is the string "?NNN" or ":AAA" or "@AAA" or "$AAA"** respectively.** In other words, the initial ":" or "$" or "@" or "?"** is included as part of the name.)^** ^Parameters of the form "?" without a following integer have no name** and are referred to as "nameless" or "anonymous parameters".**** ^The first host parameter has an index of 1, not 0.**** ^If the value N is out of range or if the N-th parameter is** nameless, then NULL is returned. ^The returned string is** always in UTF-8 encoding even if the named parameter was** originally specified as UTF-16 in [sqlite3_prepare16()] or** [sqlite3_prepare16_v2()].**** See also: [sqlite3_bind_blob|sqlite3_bind()],** [sqlite3_bind_parameter_count()], and** [sqlite3_bind_parameter_index()].*/SQLITE_APIconstchar*sqlite3_bind_parameter_name(sqlite3_stmt*,int);/*** CAPI3REF: Index Of A Parameter With A Given Name** METHOD: sqlite3_stmt**** ^Return the index of an SQL parameter given its name. ^The** index value returned is suitable for use as the second** parameter to [sqlite3_bind_blob|sqlite3_bind()]. ^A zero** is returned if no matching parameter is found. ^The parameter** name must be given in UTF-8 even if the original statement** was prepared from UTF-16 text using [sqlite3_prepare16_v2()].**** See also: [sqlite3_bind_blob|sqlite3_bind()],** [sqlite3_bind_parameter_count()], and** [sqlite3_bind_parameter_name()].*/SQLITE_APIintsqlite3_bind_parameter_index(sqlite3_stmt*,constchar*zName);/*** CAPI3REF: Reset All Bindings On A Prepared Statement** METHOD: sqlite3_stmt**** ^Contrary to the intuition of many, [sqlite3_reset()] does not reset** the [sqlite3_bind_blob | bindings] on a [prepared statement].** ^Use this routine to reset all host parameters to NULL.*/SQLITE_APIintsqlite3_clear_bindings(sqlite3_stmt*);/*** CAPI3REF: Number Of Columns In A Result Set** METHOD: sqlite3_stmt**** ^Return the number of columns in the result set returned by the** [prepared statement]. ^This routine returns 0 if pStmt is an SQL** statement that does not return data (for example an [UPDATE]).**** See also: [sqlite3_data_count()]*/SQLITE_APIintsqlite3_column_count(sqlite3_stmt*pStmt);/*** CAPI3REF: Column Names In A Result Set** METHOD: sqlite3_stmt**** ^These routines return the name assigned to a particular column** in the result set of a [SELECT] statement. ^The sqlite3_column_name()** interface returns a pointer to a zero-terminated UTF-8 string** and sqlite3_column_name16() returns a pointer to a zero-terminated** UTF-16 string. ^The first parameter is the [prepared statement]** that implements the [SELECT] statement. ^The second parameter is the** column number. ^The leftmost column is number 0.**** ^The returned string pointer is valid until either the [prepared statement]** is destroyed by [sqlite3_finalize()] or until the statement is automatically** reprepared by the first call to [sqlite3_step()] for a particular run** or until the next call to** sqlite3_column_name() or sqlite3_column_name16() on the same column.**** ^If sqlite3_malloc() fails during the processing of either routine** (for example during a conversion from UTF-8 to UTF-16) then a** NULL pointer is returned.**** ^The name of a result column is the value of the "AS" clause for** that column, if there is an AS clause. If there is no AS clause** then the name of the column is unspecified and may change from** one release of SQLite to the next.*/SQLITE_APIconstchar*sqlite3_column_name(sqlite3_stmt*,intN);SQLITE_APIconstvoid*sqlite3_column_name16(sqlite3_stmt*,intN);/*** CAPI3REF: Source Of Data In A Query Result** METHOD: sqlite3_stmt**** ^These routines provide a means to determine the database, table, and** table column that is the origin of a particular result column in** [SELECT] statement.** ^The name of the database or table or column can be returned as** either a UTF-8 or UTF-16 string. ^The _database_ routines return** the database name, the _table_ routines return the table name, and** the origin_ routines return the column name.** ^The returned string is valid until the [prepared statement] is destroyed** using [sqlite3_finalize()] or until the statement is automatically** reprepared by the first call to [sqlite3_step()] for a particular run** or until the same information is requested** again in a different encoding.**** ^The names returned are the original un-aliased names of the** database, table, and column.**** ^The first argument to these interfaces is a [prepared statement].** ^These functions return information about the Nth result column returned by** the statement, where N is the second function argument.** ^The left-most column is column 0 for these routines.**** ^If the Nth column returned by the statement is an expression or** subquery and is not a column value, then all of these functions return** NULL. ^These routine might also return NULL if a memory allocation error** occurs. ^Otherwise, they return the name of the attached database, table,** or column that query result column was extracted from.**** ^As with all other SQLite APIs, those whose names end with "16" return** UTF-16 encoded strings and the other functions return UTF-8.**** ^These APIs are only available if the library was compiled with the** [SQLITE_ENABLE_COLUMN_METADATA] C-preprocessor symbol.**** If two or more threads call one or more of these routines against the same** prepared statement and column at the same time then the results are** undefined.**** If two or more threads call one or more** [sqlite3_column_database_name | column metadata interfaces]** for the same [prepared statement] and result column** at the same time then the results are undefined.*/SQLITE_APIconstchar*sqlite3_column_database_name(sqlite3_stmt*,int);SQLITE_APIconstvoid*sqlite3_column_database_name16(sqlite3_stmt*,int);SQLITE_APIconstchar*sqlite3_column_table_name(sqlite3_stmt*,int);SQLITE_APIconstvoid*sqlite3_column_table_name16(sqlite3_stmt*,int);SQLITE_APIconstchar*sqlite3_column_origin_name(sqlite3_stmt*,int);SQLITE_APIconstvoid*sqlite3_column_origin_name16(sqlite3_stmt*,int);/*** CAPI3REF: Declared Datatype Of A Query Result** METHOD: sqlite3_stmt**** ^(The first parameter is a [prepared statement].** If this statement is a [SELECT] statement and the Nth column of the** returned result set of that [SELECT] is a table column (not an** expression or subquery) then the declared type of the table** column is returned.)^ ^If the Nth column of the result set is an** expression or subquery, then a NULL pointer is returned.** ^The returned string is always UTF-8 encoded.**** ^(For example, given the database schema:**** CREATE TABLE t1(c1 VARIANT);**** and the following statement to be compiled:**** SELECT c1 + 1, c1 FROM t1;**** this routine would return the string "VARIANT" for the second result** column (i==1), and a NULL pointer for the first result column (i==0).)^**** ^SQLite uses dynamic run-time typing. ^So just because a column** is declared to contain a particular type does not mean that the** data stored in that column is of the declared type. SQLite is** strongly typed, but the typing is dynamic not static. ^Type** is associated with individual values, not with the containers** used to hold those values.*/SQLITE_APIconstchar*sqlite3_column_decltype(sqlite3_stmt*,int);SQLITE_APIconstvoid*sqlite3_column_decltype16(sqlite3_stmt*,int);/*** CAPI3REF: Evaluate An SQL Statement** METHOD: sqlite3_stmt**** After a [prepared statement] has been prepared using either** [sqlite3_prepare_v2()] or [sqlite3_prepare16_v2()] or one of the legacy** interfaces [sqlite3_prepare()] or [sqlite3_prepare16()], this function** must be called one or more times to evaluate the statement.**** The details of the behavior of the sqlite3_step() interface depend** on whether the statement was prepared using the newer "v2" interface** [sqlite3_prepare_v2()] and [sqlite3_prepare16_v2()] or the older legacy** interface [sqlite3_prepare()] and [sqlite3_prepare16()]. The use of the** new "v2" interface is recommended for new applications but the legacy** interface will continue to be supported.**** ^In the legacy interface, the return value will be either [SQLITE_BUSY],** [SQLITE_DONE], [SQLITE_ROW], [SQLITE_ERROR], or [SQLITE_MISUSE].** ^With the "v2" interface, any of the other [result codes] or** [extended result codes] might be returned as well.**** ^[SQLITE_BUSY] means that the database engine was unable to acquire the** database locks it needs to do its job. ^If the statement is a [COMMIT]** or occurs outside of an explicit transaction, then you can retry the** statement. If the statement is not a [COMMIT] and occurs within an** explicit transaction then you should rollback the transaction before** continuing.**** ^[SQLITE_DONE] means that the statement has finished executing** successfully. sqlite3_step() should not be called again on this virtual** machine without first calling [sqlite3_reset()] to reset the virtual** machine back to its initial state.**** ^If the SQL statement being executed returns any data, then [SQLITE_ROW]** is returned each time a new row of data is ready for processing by the** caller. The values may be accessed using the [column access functions].** sqlite3_step() is called again to retrieve the next row of data.**** ^[SQLITE_ERROR] means that a run-time error (such as a constraint** violation) has occurred. sqlite3_step() should not be called again on** the VM. More information may be found by calling [sqlite3_errmsg()].** ^With the legacy interface, a more specific error code (for example,** [SQLITE_INTERRUPT], [SQLITE_SCHEMA], [SQLITE_CORRUPT], and so forth)** can be obtained by calling [sqlite3_reset()] on the** [prepared statement]. ^In the "v2" interface,** the more specific error code is returned directly by sqlite3_step().**** [SQLITE_MISUSE] means that the this routine was called inappropriately.** Perhaps it was called on a [prepared statement] that has** already been [sqlite3_finalize | finalized] or on one that had** previously returned [SQLITE_ERROR] or [SQLITE_DONE]. Or it could** be the case that the same database connection is being used by two or** more threads at the same moment in time.**** For all versions of SQLite up to and including 3.6.23.1, a call to** [sqlite3_reset()] was required after sqlite3_step() returned anything** other than [SQLITE_ROW] before any subsequent invocation of** sqlite3_step(). Failure to reset the prepared statement using ** [sqlite3_reset()] would result in an [SQLITE_MISUSE] return from** sqlite3_step(). But after [version 3.6.23.1] ([dateof:3.6.23.1],** sqlite3_step() began** calling [sqlite3_reset()] automatically in this circumstance rather** than returning [SQLITE_MISUSE]. This is not considered a compatibility** break because any application that ever receives an SQLITE_MISUSE error** is broken by definition. The [SQLITE_OMIT_AUTORESET] compile-time option** can be used to restore the legacy behavior.**** <b>Goofy Interface Alert:</b> In the legacy interface, the sqlite3_step()** API always returns a generic error code, [SQLITE_ERROR], following any** error other than [SQLITE_BUSY] and [SQLITE_MISUSE]. You must call** [sqlite3_reset()] or [sqlite3_finalize()] in order to find one of the** specific [error codes] that better describes the error.** We admit that this is a goofy design. The problem has been fixed** with the "v2" interface. If you prepare all of your SQL statements** using either [sqlite3_prepare_v2()] or [sqlite3_prepare16_v2()] instead** of the legacy [sqlite3_prepare()] and [sqlite3_prepare16()] interfaces,** then the more specific [error codes] are returned directly** by sqlite3_step(). The use of the "v2" interface is recommended.*/SQLITE_APIintsqlite3_step(sqlite3_stmt*);/*** CAPI3REF: Number of columns in a result set** METHOD: sqlite3_stmt**** ^The sqlite3_data_count(P) interface returns the number of columns in the** current row of the result set of [prepared statement] P.** ^If prepared statement P does not have results ready to return** (via calls to the [sqlite3_column_int | sqlite3_column_*()] of** interfaces) then sqlite3_data_count(P) returns 0.** ^The sqlite3_data_count(P) routine also returns 0 if P is a NULL pointer.** ^The sqlite3_data_count(P) routine returns 0 if the previous call to** [sqlite3_step](P) returned [SQLITE_DONE]. ^The sqlite3_data_count(P)** will return non-zero if previous call to [sqlite3_step](P) returned** [SQLITE_ROW], except in the case of the [PRAGMA incremental_vacuum]** where it always returns zero since each step of that multi-step** pragma returns 0 columns of data.**** See also: [sqlite3_column_count()]*/SQLITE_APIintsqlite3_data_count(sqlite3_stmt*pStmt);/*** CAPI3REF: Fundamental Datatypes** KEYWORDS: SQLITE_TEXT**** ^(Every value in SQLite has one of five fundamental datatypes:**** <ul>** <li> 64-bit signed integer** <li> 64-bit IEEE floating point number** <li> string** <li> BLOB** <li> NULL** </ul>)^**** These constants are codes for each of those types.**** Note that the SQLITE_TEXT constant was also used in SQLite version 2** for a completely different meaning. Software that links against both** SQLite version 2 and SQLite version 3 should use SQLITE3_TEXT, not** SQLITE_TEXT.*/#define SQLITE_INTEGER 1#define SQLITE_FLOAT 2#define SQLITE_BLOB 4#define SQLITE_NULL 5#ifdef SQLITE_TEXT# undef SQLITE_TEXT#else# define SQLITE_TEXT 3#endif#define SQLITE3_TEXT 3/*** CAPI3REF: Result Values From A Query** KEYWORDS: {column access functions}** METHOD: sqlite3_stmt**** ^These routines return information about a single column of the current** result row of a query. ^In every case the first argument is a pointer** to the [prepared statement] that is being evaluated (the [sqlite3_stmt*]** that was returned from [sqlite3_prepare_v2()] or one of its variants)** and the second argument is the index of the column for which information** should be returned. ^The leftmost column of the result set has the index 0.** ^The number of columns in the result can be determined using** [sqlite3_column_count()].**** If the SQL statement does not currently point to a valid row, or if the** column index is out of range, the result is undefined.** These routines may only be called when the most recent call to** [sqlite3_step()] has returned [SQLITE_ROW] and neither** [sqlite3_reset()] nor [sqlite3_finalize()] have been called subsequently.** If any of these routines are called after [sqlite3_reset()] or** [sqlite3_finalize()] or after [sqlite3_step()] has returned** something other than [SQLITE_ROW], the results are undefined.** If [sqlite3_step()] or [sqlite3_reset()] or [sqlite3_finalize()]** are called from a different thread while any of these routines** are pending, then the results are undefined.**** ^The sqlite3_column_type() routine returns the** [SQLITE_INTEGER | datatype code] for the initial data type** of the result column. ^The returned value is one of [SQLITE_INTEGER],** [SQLITE_FLOAT], [SQLITE_TEXT], [SQLITE_BLOB], or [SQLITE_NULL]. The value** returned by sqlite3_column_type() is only meaningful if no type** conversions have occurred as described below. After a type conversion,** the value returned by sqlite3_column_type() is undefined. Future** versions of SQLite may change the behavior of sqlite3_column_type()** following a type conversion.**** ^If the result is a BLOB or UTF-8 string then the sqlite3_column_bytes()** routine returns the number of bytes in that BLOB or string.** ^If the result is a UTF-16 string, then sqlite3_column_bytes() converts** the string to UTF-8 and then returns the number of bytes.** ^If the result is a numeric value then sqlite3_column_bytes() uses** [sqlite3_snprintf()] to convert that value to a UTF-8 string and returns** the number of bytes in that string.** ^If the result is NULL, then sqlite3_column_bytes() returns zero.**** ^If the result is a BLOB or UTF-16 string then the sqlite3_column_bytes16()** routine returns the number of bytes in that BLOB or string.** ^If the result is a UTF-8 string, then sqlite3_column_bytes16() converts** the string to UTF-16 and then returns the number of bytes.** ^If the result is a numeric value then sqlite3_column_bytes16() uses** [sqlite3_snprintf()] to convert that value to a UTF-16 string and returns** the number of bytes in that string.** ^If the result is NULL, then sqlite3_column_bytes16() returns zero.**** ^The values returned by [sqlite3_column_bytes()] and ** [sqlite3_column_bytes16()] do not include the zero terminators at the end** of the string. ^For clarity: the values returned by** [sqlite3_column_bytes()] and [sqlite3_column_bytes16()] are the number of** bytes in the string, not the number of characters.**** ^Strings returned by sqlite3_column_text() and sqlite3_column_text16(),** even empty strings, are always zero-terminated. ^The return** value from sqlite3_column_blob() for a zero-length BLOB is a NULL pointer.**** <b>Warning:</b> ^The object returned by [sqlite3_column_value()] is an** [unprotected sqlite3_value] object. In a multithreaded environment,** an unprotected sqlite3_value object may only be used safely with** [sqlite3_bind_value()] and [sqlite3_result_value()].** If the [unprotected sqlite3_value] object returned by** [sqlite3_column_value()] is used in any other way, including calls** to routines like [sqlite3_value_int()], [sqlite3_value_text()],** or [sqlite3_value_bytes()], the behavior is not threadsafe.**** These routines attempt to convert the value where appropriate. ^For** example, if the internal representation is FLOAT and a text result** is requested, [sqlite3_snprintf()] is used internally to perform the** conversion automatically. ^(The following table details the conversions** that are applied:**** <blockquote>** <table border="1">** <tr><th> Internal<br>Type <th> Requested<br>Type <th> Conversion**** <tr><td> NULL <td> INTEGER <td> Result is 0** <tr><td> NULL <td> FLOAT <td> Result is 0.0** <tr><td> NULL <td> TEXT <td> Result is a NULL pointer** <tr><td> NULL <td> BLOB <td> Result is a NULL pointer** <tr><td> INTEGER <td> FLOAT <td> Convert from integer to float** <tr><td> INTEGER <td> TEXT <td> ASCII rendering of the integer** <tr><td> INTEGER <td> BLOB <td> Same as INTEGER->TEXT** <tr><td> FLOAT <td> INTEGER <td> [CAST] to INTEGER** <tr><td> FLOAT <td> TEXT <td> ASCII rendering of the float** <tr><td> FLOAT <td> BLOB <td> [CAST] to BLOB** <tr><td> TEXT <td> INTEGER <td> [CAST] to INTEGER** <tr><td> TEXT <td> FLOAT <td> [CAST] to REAL** <tr><td> TEXT <td> BLOB <td> No change** <tr><td> BLOB <td> INTEGER <td> [CAST] to INTEGER** <tr><td> BLOB <td> FLOAT <td> [CAST] to REAL** <tr><td> BLOB <td> TEXT <td> Add a zero terminator if needed** </table>** </blockquote>)^**** Note that when type conversions occur, pointers returned by prior** calls to sqlite3_column_blob(), sqlite3_column_text(), and/or** sqlite3_column_text16() may be invalidated.** Type conversions and pointer invalidations might occur** in the following cases:**** <ul>** <li> The initial content is a BLOB and sqlite3_column_text() or** sqlite3_column_text16() is called. A zero-terminator might** need to be added to the string.</li>** <li> The initial content is UTF-8 text and sqlite3_column_bytes16() or** sqlite3_column_text16() is called. The content must be converted** to UTF-16.</li>** <li> The initial content is UTF-16 text and sqlite3_column_bytes() or** sqlite3_column_text() is called. The content must be converted** to UTF-8.</li>** </ul>**** ^Conversions between UTF-16be and UTF-16le are always done in place and do** not invalidate a prior pointer, though of course the content of the buffer** that the prior pointer references will have been modified. Other kinds** of conversion are done in place when it is possible, but sometimes they** are not possible and in those cases prior pointers are invalidated.**** The safest policy is to invoke these routines** in one of the following ways:**** <ul>** <li>sqlite3_column_text() followed by sqlite3_column_bytes()</li>** <li>sqlite3_column_blob() followed by sqlite3_column_bytes()</li>** <li>sqlite3_column_text16() followed by sqlite3_column_bytes16()</li>** </ul>**** In other words, you should call sqlite3_column_text(),** sqlite3_column_blob(), or sqlite3_column_text16() first to force the result** into the desired format, then invoke sqlite3_column_bytes() or** sqlite3_column_bytes16() to find the size of the result. Do not mix calls** to sqlite3_column_text() or sqlite3_column_blob() with calls to** sqlite3_column_bytes16(), and do not mix calls to sqlite3_column_text16()** with calls to sqlite3_column_bytes().**** ^The pointers returned are valid until a type conversion occurs as** described above, or until [sqlite3_step()] or [sqlite3_reset()] or** [sqlite3_finalize()] is called. ^The memory space used to hold strings** and BLOBs is freed automatically. Do <em>not</em> pass the pointers returned** from [sqlite3_column_blob()], [sqlite3_column_text()], etc. into** [sqlite3_free()].**** ^(If a memory allocation error occurs during the evaluation of any** of these routines, a default value is returned. The default value** is either the integer 0, the floating point number 0.0, or a NULL** pointer. Subsequent calls to [sqlite3_errcode()] will return** [SQLITE_NOMEM].)^*/SQLITE_APIconstvoid*sqlite3_column_blob(sqlite3_stmt*,intiCol);SQLITE_APIintsqlite3_column_bytes(sqlite3_stmt*,intiCol);SQLITE_APIintsqlite3_column_bytes16(sqlite3_stmt*,intiCol);SQLITE_APIdoublesqlite3_column_double(sqlite3_stmt*,intiCol);SQLITE_APIintsqlite3_column_int(sqlite3_stmt*,intiCol);SQLITE_APIsqlite3_int64sqlite3_column_int64(sqlite3_stmt*,intiCol);SQLITE_APIconstunsignedchar*sqlite3_column_text(sqlite3_stmt*,intiCol);SQLITE_APIconstvoid*sqlite3_column_text16(sqlite3_stmt*,intiCol);SQLITE_APIintsqlite3_column_type(sqlite3_stmt*,intiCol);SQLITE_APIsqlite3_value*sqlite3_column_value(sqlite3_stmt*,intiCol);/*** CAPI3REF: Destroy A Prepared Statement Object** DESTRUCTOR: sqlite3_stmt**** ^The sqlite3_finalize() function is called to delete a [prepared statement].** ^If the most recent evaluation of the statement encountered no errors** or if the statement is never been evaluated, then sqlite3_finalize() returns** SQLITE_OK. ^If the most recent evaluation of statement S failed, then** sqlite3_finalize(S) returns the appropriate [error code] or** [extended error code].**** ^The sqlite3_finalize(S) routine can be called at any point during** the life cycle of [prepared statement] S:** before statement S is ever evaluated, after** one or more calls to [sqlite3_reset()], or after any call** to [sqlite3_step()] regardless of whether or not the statement has** completed execution.**** ^Invoking sqlite3_finalize() on a NULL pointer is a harmless no-op.**** The application must finalize every [prepared statement] in order to avoid** resource leaks. It is a grievous error for the application to try to use** a prepared statement after it has been finalized. Any use of a prepared** statement after it has been finalized can result in undefined and** undesirable behavior such as segfaults and heap corruption.*/SQLITE_APIintsqlite3_finalize(sqlite3_stmt*pStmt);/*** CAPI3REF: Reset A Prepared Statement Object** METHOD: sqlite3_stmt**** The sqlite3_reset() function is called to reset a [prepared statement]** object back to its initial state, ready to be re-executed.** ^Any SQL statement variables that had values bound to them using** the [sqlite3_bind_blob | sqlite3_bind_*() API] retain their values.** Use [sqlite3_clear_bindings()] to reset the bindings.**** ^The [sqlite3_reset(S)] interface resets the [prepared statement] S** back to the beginning of its program.**** ^If the most recent call to [sqlite3_step(S)] for the** [prepared statement] S returned [SQLITE_ROW] or [SQLITE_DONE],** or if [sqlite3_step(S)] has never before been called on S,** then [sqlite3_reset(S)] returns [SQLITE_OK].**** ^If the most recent call to [sqlite3_step(S)] for the** [prepared statement] S indicated an error, then** [sqlite3_reset(S)] returns an appropriate [error code].**** ^The [sqlite3_reset(S)] interface does not change the values** of any [sqlite3_bind_blob|bindings] on the [prepared statement] S.*/SQLITE_APIintsqlite3_reset(sqlite3_stmt*pStmt);/*** CAPI3REF: Create Or Redefine SQL Functions** KEYWORDS: {function creation routines}** KEYWORDS: {application-defined SQL function}** KEYWORDS: {application-defined SQL functions}** METHOD: sqlite3**** ^These functions (collectively known as "function creation routines")** are used to add SQL functions or aggregates or to redefine the behavior** of existing SQL functions or aggregates. The only differences between** these routines are the text encoding expected for** the second parameter (the name of the function being created)** and the presence or absence of a destructor callback for** the application data pointer.**** ^The first parameter is the [database connection] to which the SQL** function is to be added. ^If an application uses more than one database** connection then application-defined SQL functions must be added** to each database connection separately.**** ^The second parameter is the name of the SQL function to be created or** redefined. ^The length of the name is limited to 255 bytes in a UTF-8** representation, exclusive of the zero-terminator. ^Note that the name** length limit is in UTF-8 bytes, not characters nor UTF-16 bytes. ** ^Any attempt to create a function with a longer name** will result in [SQLITE_MISUSE] being returned.**** ^The third parameter (nArg)** is the number of arguments that the SQL function or** aggregate takes. ^If this parameter is -1, then the SQL function or** aggregate may take any number of arguments between 0 and the limit** set by [sqlite3_limit]([SQLITE_LIMIT_FUNCTION_ARG]). If the third** parameter is less than -1 or greater than 127 then the behavior is** undefined.**** ^The fourth parameter, eTextRep, specifies what** [SQLITE_UTF8 | text encoding] this SQL function prefers for** its parameters. The application should set this parameter to** [SQLITE_UTF16LE] if the function implementation invokes ** [sqlite3_value_text16le()] on an input, or [SQLITE_UTF16BE] if the** implementation invokes [sqlite3_value_text16be()] on an input, or** [SQLITE_UTF16] if [sqlite3_value_text16()] is used, or [SQLITE_UTF8]** otherwise. ^The same SQL function may be registered multiple times using** different preferred text encodings, with different implementations for** each encoding.** ^When multiple implementations of the same function are available, SQLite** will pick the one that involves the least amount of data conversion.**** ^The fourth parameter may optionally be ORed with [SQLITE_DETERMINISTIC]** to signal that the function will always return the same result given** the same inputs within a single SQL statement. Most SQL functions are** deterministic. The built-in [random()] SQL function is an example of a** function that is not deterministic. The SQLite query planner is able to** perform additional optimizations on deterministic functions, so use** of the [SQLITE_DETERMINISTIC] flag is recommended where possible.**** ^(The fifth parameter is an arbitrary pointer. The implementation of the** function can gain access to this pointer using [sqlite3_user_data()].)^**** ^The sixth, seventh and eighth parameters, xFunc, xStep and xFinal, are** pointers to C-language functions that implement the SQL function or** aggregate. ^A scalar SQL function requires an implementation of the xFunc** callback only; NULL pointers must be passed as the xStep and xFinal** parameters. ^An aggregate SQL function requires an implementation of xStep** and xFinal and NULL pointer must be passed for xFunc. ^To delete an existing** SQL function or aggregate, pass NULL pointers for all three function** callbacks.**** ^(If the ninth parameter to sqlite3_create_function_v2() is not NULL,** then it is destructor for the application data pointer. ** The destructor is invoked when the function is deleted, either by being** overloaded or when the database connection closes.)^** ^The destructor is also invoked if the call to** sqlite3_create_function_v2() fails.** ^When the destructor callback of the tenth parameter is invoked, it** is passed a single argument which is a copy of the application data ** pointer which was the fifth parameter to sqlite3_create_function_v2().**** ^It is permitted to register multiple implementations of the same** functions with the same name but with either differing numbers of** arguments or differing preferred text encodings. ^SQLite will use** the implementation that most closely matches the way in which the** SQL function is used. ^A function implementation with a non-negative** nArg parameter is a better match than a function implementation with** a negative nArg. ^A function where the preferred text encoding** matches the database encoding is a better** match than a function where the encoding is different. ** ^A function where the encoding difference is between UTF16le and UTF16be** is a closer match than a function where the encoding difference is** between UTF8 and UTF16.**** ^Built-in functions may be overloaded by new application-defined functions.**** ^An application-defined function is permitted to call other** SQLite interfaces. However, such calls must not** close the database connection nor finalize or reset the prepared** statement in which the function is running.*/SQLITE_APIintsqlite3_create_function(sqlite3*db,constchar*zFunctionName,intnArg,inteTextRep,void*pApp,void(*xFunc)(sqlite3_context*,int,sqlite3_value**),void(*xStep)(sqlite3_context*,int,sqlite3_value**),void(*xFinal)(sqlite3_context*));SQLITE_APIintsqlite3_create_function16(sqlite3*db,constvoid*zFunctionName,intnArg,inteTextRep,void*pApp,void(*xFunc)(sqlite3_context*,int,sqlite3_value**),void(*xStep)(sqlite3_context*,int,sqlite3_value**),void(*xFinal)(sqlite3_context*));SQLITE_APIintsqlite3_create_function_v2(sqlite3*db,constchar*zFunctionName,intnArg,inteTextRep,void*pApp,void(*xFunc)(sqlite3_context*,int,sqlite3_value**),void(*xStep)(sqlite3_context*,int,sqlite3_value**),void(*xFinal)(sqlite3_context*),void(*xDestroy)(void*));/*** CAPI3REF: Text Encodings**** These constant define integer codes that represent the various** text encodings supported by SQLite.*/#define SQLITE_UTF8 1 /* IMP: R-37514-35566 */#define SQLITE_UTF16LE 2 /* IMP: R-03371-37637 */#define SQLITE_UTF16BE 3 /* IMP: R-51971-34154 */#define SQLITE_UTF16 4 /* Use native byte order */#define SQLITE_ANY 5 /* Deprecated */#define SQLITE_UTF16_ALIGNED 8 /* sqlite3_create_collation only *//*** CAPI3REF: Function Flags**** These constants may be ORed together with the ** [SQLITE_UTF8 | preferred text encoding] as the fourth argument** to [sqlite3_create_function()], [sqlite3_create_function16()], or** [sqlite3_create_function_v2()].*/#define SQLITE_DETERMINISTIC 0x800/*** CAPI3REF: Deprecated Functions** DEPRECATED**** These functions are [deprecated]. In order to maintain** backwards compatibility with older code, these functions continue ** to be supported. However, new applications should avoid** the use of these functions. To encourage programmers to avoid** these functions, we will not explain what they do.*/#ifndef SQLITE_OMIT_DEPRECATEDSQLITE_APISQLITE_DEPRECATEDintsqlite3_aggregate_count(sqlite3_context*);SQLITE_APISQLITE_DEPRECATEDintsqlite3_expired(sqlite3_stmt*);SQLITE_APISQLITE_DEPRECATEDintsqlite3_transfer_bindings(sqlite3_stmt*,sqlite3_stmt*);SQLITE_APISQLITE_DEPRECATEDintsqlite3_global_recover(void);SQLITE_APISQLITE_DEPRECATEDvoidsqlite3_thread_cleanup(void);SQLITE_APISQLITE_DEPRECATEDintsqlite3_memory_alarm(void(*)(void*,sqlite3_int64,int),void*,sqlite3_int64);#endif/*** CAPI3REF: Obtaining SQL Values** METHOD: sqlite3_value**** The C-language implementation of SQL functions and aggregates uses** this set of interface routines to access the parameter values on** the function or aggregate. **** The xFunc (for scalar functions) or xStep (for aggregates) parameters** to [sqlite3_create_function()] and [sqlite3_create_function16()]** define callbacks that implement the SQL functions and aggregates.** The 3rd parameter to these callbacks is an array of pointers to** [protected sqlite3_value] objects. There is one [sqlite3_value] object for** each parameter to the SQL function. These routines are used to** extract values from the [sqlite3_value] objects.**** These routines work only with [protected sqlite3_value] objects.** Any attempt to use these routines on an [unprotected sqlite3_value]** object results in undefined behavior.**** ^These routines work just like the corresponding [column access functions]** except that these routines take a single [protected sqlite3_value] object** pointer instead of a [sqlite3_stmt*] pointer and an integer column number.**** ^The sqlite3_value_text16() interface extracts a UTF-16 string** in the native byte-order of the host machine. ^The** sqlite3_value_text16be() and sqlite3_value_text16le() interfaces** extract UTF-16 strings as big-endian and little-endian respectively.**** ^(The sqlite3_value_numeric_type() interface attempts to apply** numeric affinity to the value. This means that an attempt is** made to convert the value to an integer or floating point. If** such a conversion is possible without loss of information (in other** words, if the value is a string that looks like a number)** then the conversion is performed. Otherwise no conversion occurs.** The [SQLITE_INTEGER | datatype] after conversion is returned.)^**** Please pay particular attention to the fact that the pointer returned** from [sqlite3_value_blob()], [sqlite3_value_text()], or** [sqlite3_value_text16()] can be invalidated by a subsequent call to** [sqlite3_value_bytes()], [sqlite3_value_bytes16()], [sqlite3_value_text()],** or [sqlite3_value_text16()].**** These routines must be called from the same thread as** the SQL function that supplied the [sqlite3_value*] parameters.*/SQLITE_APIconstvoid*sqlite3_value_blob(sqlite3_value*);SQLITE_APIintsqlite3_value_bytes(sqlite3_value*);SQLITE_APIintsqlite3_value_bytes16(sqlite3_value*);SQLITE_APIdoublesqlite3_value_double(sqlite3_value*);SQLITE_APIintsqlite3_value_int(sqlite3_value*);SQLITE_APIsqlite3_int64sqlite3_value_int64(sqlite3_value*);SQLITE_APIconstunsignedchar*sqlite3_value_text(sqlite3_value*);SQLITE_APIconstvoid*sqlite3_value_text16(sqlite3_value*);SQLITE_APIconstvoid*sqlite3_value_text16le(sqlite3_value*);SQLITE_APIconstvoid*sqlite3_value_text16be(sqlite3_value*);SQLITE_APIintsqlite3_value_type(sqlite3_value*);SQLITE_APIintsqlite3_value_numeric_type(sqlite3_value*);/*** CAPI3REF: Finding The Subtype Of SQL Values** METHOD: sqlite3_value**** The sqlite3_value_subtype(V) function returns the subtype for** an [application-defined SQL function] argument V. The subtype** information can be used to pass a limited amount of context from** one SQL function to another. Use the [sqlite3_result_subtype()]** routine to set the subtype for the return value of an SQL function.**** SQLite makes no use of subtype itself. It merely passes the subtype** from the result of one [application-defined SQL function] into the** input of another.*/SQLITE_APIunsignedintsqlite3_value_subtype(sqlite3_value*);/*** CAPI3REF: Copy And Free SQL Values** METHOD: sqlite3_value**** ^The sqlite3_value_dup(V) interface makes a copy of the [sqlite3_value]** object D and returns a pointer to that copy. ^The [sqlite3_value] returned** is a [protected sqlite3_value] object even if the input is not.** ^The sqlite3_value_dup(V) interface returns NULL if V is NULL or if a** memory allocation fails.**** ^The sqlite3_value_free(V) interface frees an [sqlite3_value] object** previously obtained from [sqlite3_value_dup()]. ^If V is a NULL pointer** then sqlite3_value_free(V) is a harmless no-op.*/SQLITE_APIsqlite3_value*sqlite3_value_dup(constsqlite3_value*);SQLITE_APIvoidsqlite3_value_free(sqlite3_value*);/*** CAPI3REF: Obtain Aggregate Function Context** METHOD: sqlite3_context**** Implementations of aggregate SQL functions use this** routine to allocate memory for storing their state.**** ^The first time the sqlite3_aggregate_context(C,N) routine is called ** for a particular aggregate function, SQLite** allocates N of memory, zeroes out that memory, and returns a pointer** to the new memory. ^On second and subsequent calls to** sqlite3_aggregate_context() for the same aggregate function instance,** the same buffer is returned. Sqlite3_aggregate_context() is normally** called once for each invocation of the xStep callback and then one** last time when the xFinal callback is invoked. ^(When no rows match** an aggregate query, the xStep() callback of the aggregate function** implementation is never called and xFinal() is called exactly once.** In those cases, sqlite3_aggregate_context() might be called for the** first time from within xFinal().)^**** ^The sqlite3_aggregate_context(C,N) routine returns a NULL pointer ** when first called if N is less than or equal to zero or if a memory** allocate error occurs.**** ^(The amount of space allocated by sqlite3_aggregate_context(C,N) is** determined by the N parameter on first successful call. Changing the** value of N in subsequent call to sqlite3_aggregate_context() within** the same aggregate function instance will not resize the memory** allocation.)^ Within the xFinal callback, it is customary to set** N=0 in calls to sqlite3_aggregate_context(C,N) so that no ** pointless memory allocations occur.**** ^SQLite automatically frees the memory allocated by ** sqlite3_aggregate_context() when the aggregate query concludes.**** The first parameter must be a copy of the** [sqlite3_context | SQL function context] that is the first parameter** to the xStep or xFinal callback routine that implements the aggregate** function.**** This routine must be called from the same thread in which** the aggregate SQL function is running.*/SQLITE_APIvoid*sqlite3_aggregate_context(sqlite3_context*,intnBytes);/*** CAPI3REF: User Data For Functions** METHOD: sqlite3_context**** ^The sqlite3_user_data() interface returns a copy of** the pointer that was the pUserData parameter (the 5th parameter)** of the [sqlite3_create_function()]** and [sqlite3_create_function16()] routines that originally** registered the application defined function.**** This routine must be called from the same thread in which** the application-defined function is running.*/SQLITE_APIvoid*sqlite3_user_data(sqlite3_context*);/*** CAPI3REF: Database Connection For Functions** METHOD: sqlite3_context**** ^The sqlite3_context_db_handle() interface returns a copy of** the pointer to the [database connection] (the 1st parameter)** of the [sqlite3_create_function()]** and [sqlite3_create_function16()] routines that originally** registered the application defined function.*/SQLITE_APIsqlite3*sqlite3_context_db_handle(sqlite3_context*);/*** CAPI3REF: Function Auxiliary Data** METHOD: sqlite3_context**** These functions may be used by (non-aggregate) SQL functions to** associate metadata with argument values. If the same value is passed to** multiple invocations of the same SQL function during query execution, under** some circumstances the associated metadata may be preserved. An example** of where this might be useful is in a regular-expression matching** function. The compiled version of the regular expression can be stored as** metadata associated with the pattern string. ** Then as long as the pattern string remains the same,** the compiled regular expression can be reused on multiple** invocations of the same function.**** ^The sqlite3_get_auxdata() interface returns a pointer to the metadata** associated by the sqlite3_set_auxdata() function with the Nth argument** value to the application-defined function. ^If there is no metadata** associated with the function argument, this sqlite3_get_auxdata() interface** returns a NULL pointer.**** ^The sqlite3_set_auxdata(C,N,P,X) interface saves P as metadata for the N-th** argument of the application-defined function. ^Subsequent** calls to sqlite3_get_auxdata(C,N) return P from the most recent** sqlite3_set_auxdata(C,N,P,X) call if the metadata is still valid or** NULL if the metadata has been discarded.** ^After each call to sqlite3_set_auxdata(C,N,P,X) where X is not NULL,** SQLite will invoke the destructor function X with parameter P exactly** once, when the metadata is discarded.** SQLite is free to discard the metadata at any time, including: <ul>** <li> ^(when the corresponding function parameter changes)^, or** <li> ^(when [sqlite3_reset()] or [sqlite3_finalize()] is called for the** SQL statement)^, or** <li> ^(when sqlite3_set_auxdata() is invoked again on the same** parameter)^, or** <li> ^(during the original sqlite3_set_auxdata() call when a memory ** allocation error occurs.)^ </ul>**** Note the last bullet in particular. The destructor X in ** sqlite3_set_auxdata(C,N,P,X) might be called immediately, before the** sqlite3_set_auxdata() interface even returns. Hence sqlite3_set_auxdata()** should be called near the end of the function implementation and the** function implementation should not make any use of P after** sqlite3_set_auxdata() has been called.**** ^(In practice, metadata is preserved between function calls for** function parameters that are compile-time constants, including literal** values and [parameters] and expressions composed from the same.)^**** These routines must be called from the same thread in which** the SQL function is running.*/SQLITE_APIvoid*sqlite3_get_auxdata(sqlite3_context*,intN);SQLITE_APIvoidsqlite3_set_auxdata(sqlite3_context*,intN,void*,void(*)(void*));/*** CAPI3REF: Constants Defining Special Destructor Behavior**** These are special values for the destructor that is passed in as the** final argument to routines like [sqlite3_result_blob()]. ^If the destructor** argument is SQLITE_STATIC, it means that the content pointer is constant** and will never change. It does not need to be destroyed. ^The** SQLITE_TRANSIENT value means that the content will likely change in** the near future and that SQLite should make its own private copy of** the content before returning.**** The typedef is necessary to work around problems in certain** C++ compilers.*/typedefvoid(*sqlite3_destructor_type)(void*);#define SQLITE_STATIC ((sqlite3_destructor_type)0)#define SQLITE_TRANSIENT ((sqlite3_destructor_type)-1)/*** CAPI3REF: Setting The Result Of An SQL Function** METHOD: sqlite3_context**** These routines are used by the xFunc or xFinal callbacks that** implement SQL functions and aggregates. See** [sqlite3_create_function()] and [sqlite3_create_function16()]** for additional information.**** These functions work very much like the [parameter binding] family of** functions used to bind values to host parameters in prepared statements.** Refer to the [SQL parameter] documentation for additional information.**** ^The sqlite3_result_blob() interface sets the result from** an application-defined function to be the BLOB whose content is pointed** to by the second parameter and which is N bytes long where N is the** third parameter.**** ^The sqlite3_result_zeroblob(C,N) and sqlite3_result_zeroblob64(C,N)** interfaces set the result of the application-defined function to be** a BLOB containing all zero bytes and N bytes in size.**** ^The sqlite3_result_double() interface sets the result from** an application-defined function to be a floating point value specified** by its 2nd argument.**** ^The sqlite3_result_error() and sqlite3_result_error16() functions** cause the implemented SQL function to throw an exception.** ^SQLite uses the string pointed to by the** 2nd parameter of sqlite3_result_error() or sqlite3_result_error16()** as the text of an error message. ^SQLite interprets the error** message string from sqlite3_result_error() as UTF-8. ^SQLite** interprets the string from sqlite3_result_error16() as UTF-16 in native** byte order. ^If the third parameter to sqlite3_result_error()** or sqlite3_result_error16() is negative then SQLite takes as the error** message all text up through the first zero character.** ^If the third parameter to sqlite3_result_error() or** sqlite3_result_error16() is non-negative then SQLite takes that many** bytes (not characters) from the 2nd parameter as the error message.** ^The sqlite3_result_error() and sqlite3_result_error16()** routines make a private copy of the error message text before** they return. Hence, the calling function can deallocate or** modify the text after they return without harm.** ^The sqlite3_result_error_code() function changes the error code** returned by SQLite as a result of an error in a function. ^By default,** the error code is SQLITE_ERROR. ^A subsequent call to sqlite3_result_error()** or sqlite3_result_error16() resets the error code to SQLITE_ERROR.**** ^The sqlite3_result_error_toobig() interface causes SQLite to throw an** error indicating that a string or BLOB is too long to represent.**** ^The sqlite3_result_error_nomem() interface causes SQLite to throw an** error indicating that a memory allocation failed.**** ^The sqlite3_result_int() interface sets the return value** of the application-defined function to be the 32-bit signed integer** value given in the 2nd argument.** ^The sqlite3_result_int64() interface sets the return value** of the application-defined function to be the 64-bit signed integer** value given in the 2nd argument.**** ^The sqlite3_result_null() interface sets the return value** of the application-defined function to be NULL.**** ^The sqlite3_result_text(), sqlite3_result_text16(),** sqlite3_result_text16le(), and sqlite3_result_text16be() interfaces** set the return value of the application-defined function to be** a text string which is represented as UTF-8, UTF-16 native byte order,** UTF-16 little endian, or UTF-16 big endian, respectively.** ^The sqlite3_result_text64() interface sets the return value of an** application-defined function to be a text string in an encoding** specified by the fifth (and last) parameter, which must be one** of [SQLITE_UTF8], [SQLITE_UTF16], [SQLITE_UTF16BE], or [SQLITE_UTF16LE].** ^SQLite takes the text result from the application from** the 2nd parameter of the sqlite3_result_text* interfaces.** ^If the 3rd parameter to the sqlite3_result_text* interfaces** is negative, then SQLite takes result text from the 2nd parameter** through the first zero character.** ^If the 3rd parameter to the sqlite3_result_text* interfaces** is non-negative, then as many bytes (not characters) of the text** pointed to by the 2nd parameter are taken as the application-defined** function result. If the 3rd parameter is non-negative, then it** must be the byte offset into the string where the NUL terminator would** appear if the string where NUL terminated. If any NUL characters occur** in the string at a byte offset that is less than the value of the 3rd** parameter, then the resulting string will contain embedded NULs and the** result of expressions operating on strings with embedded NULs is undefined.** ^If the 4th parameter to the sqlite3_result_text* interfaces** or sqlite3_result_blob is a non-NULL pointer, then SQLite calls that** function as the destructor on the text or BLOB result when it has** finished using that result.** ^If the 4th parameter to the sqlite3_result_text* interfaces or to** sqlite3_result_blob is the special constant SQLITE_STATIC, then SQLite** assumes that the text or BLOB result is in constant space and does not** copy the content of the parameter nor call a destructor on the content** when it has finished using that result.** ^If the 4th parameter to the sqlite3_result_text* interfaces** or sqlite3_result_blob is the special constant SQLITE_TRANSIENT** then SQLite makes a copy of the result into space obtained from** from [sqlite3_malloc()] before it returns.**** ^The sqlite3_result_value() interface sets the result of** the application-defined function to be a copy of the** [unprotected sqlite3_value] object specified by the 2nd parameter. ^The** sqlite3_result_value() interface makes a copy of the [sqlite3_value]** so that the [sqlite3_value] specified in the parameter may change or** be deallocated after sqlite3_result_value() returns without harm.** ^A [protected sqlite3_value] object may always be used where an** [unprotected sqlite3_value] object is required, so either** kind of [sqlite3_value] object can be used with this interface.**** If these routines are called from within the different thread** than the one containing the application-defined function that received** the [sqlite3_context] pointer, the results are undefined.*/SQLITE_APIvoidsqlite3_result_blob(sqlite3_context*,constvoid*,int,void(*)(void*));SQLITE_APIvoidsqlite3_result_blob64(sqlite3_context*,constvoid*,sqlite3_uint64,void(*)(void*));SQLITE_APIvoidsqlite3_result_double(sqlite3_context*,double);SQLITE_APIvoidsqlite3_result_error(sqlite3_context*,constchar*,int);SQLITE_APIvoidsqlite3_result_error16(sqlite3_context*,constvoid*,int);SQLITE_APIvoidsqlite3_result_error_toobig(sqlite3_context*);SQLITE_APIvoidsqlite3_result_error_nomem(sqlite3_context*);SQLITE_APIvoidsqlite3_result_error_code(sqlite3_context*,int);SQLITE_APIvoidsqlite3_result_int(sqlite3_context*,int);SQLITE_APIvoidsqlite3_result_int64(sqlite3_context*,sqlite3_int64);SQLITE_APIvoidsqlite3_result_null(sqlite3_context*);SQLITE_APIvoidsqlite3_result_text(sqlite3_context*,constchar*,int,void(*)(void*));SQLITE_APIvoidsqlite3_result_text64(sqlite3_context*,constchar*,sqlite3_uint64,void(*)(void*),unsignedcharencoding);SQLITE_APIvoidsqlite3_result_text16(sqlite3_context*,constvoid*,int,void(*)(void*));SQLITE_APIvoidsqlite3_result_text16le(sqlite3_context*,constvoid*,int,void(*)(void*));SQLITE_APIvoidsqlite3_result_text16be(sqlite3_context*,constvoid*,int,void(*)(void*));SQLITE_APIvoidsqlite3_result_value(sqlite3_context*,sqlite3_value*);SQLITE_APIvoidsqlite3_result_zeroblob(sqlite3_context*,intn);SQLITE_APIintsqlite3_result_zeroblob64(sqlite3_context*,sqlite3_uint64n);/*** CAPI3REF: Setting The Subtype Of An SQL Function** METHOD: sqlite3_context**** The sqlite3_result_subtype(C,T) function causes the subtype of** the result from the [application-defined SQL function] with ** [sqlite3_context] C to be the value T. Only the lower 8 bits ** of the subtype T are preserved in current versions of SQLite;** higher order bits are discarded.** The number of subtype bytes preserved by SQLite might increase** in future releases of SQLite.*/SQLITE_APIvoidsqlite3_result_subtype(sqlite3_context*,unsignedint);/*** CAPI3REF: Define New Collating Sequences** METHOD: sqlite3**** ^These functions add, remove, or modify a [collation] associated** with the [database connection] specified as the first argument.**** ^The name of the collation is a UTF-8 string** for sqlite3_create_collation() and sqlite3_create_collation_v2()** and a UTF-16 string in native byte order for sqlite3_create_collation16().** ^Collation names that compare equal according to [sqlite3_strnicmp()] are** considered to be the same name.**** ^(The third argument (eTextRep) must be one of the constants:** <ul>** <li> [SQLITE_UTF8],** <li> [SQLITE_UTF16LE],** <li> [SQLITE_UTF16BE],** <li> [SQLITE_UTF16], or** <li> [SQLITE_UTF16_ALIGNED].** </ul>)^** ^The eTextRep argument determines the encoding of strings passed** to the collating function callback, xCallback.** ^The [SQLITE_UTF16] and [SQLITE_UTF16_ALIGNED] values for eTextRep** force strings to be UTF16 with native byte order.** ^The [SQLITE_UTF16_ALIGNED] value for eTextRep forces strings to begin** on an even byte address.**** ^The fourth argument, pArg, is an application data pointer that is passed** through as the first argument to the collating function callback.**** ^The fifth argument, xCallback, is a pointer to the collating function.** ^Multiple collating functions can be registered using the same name but** with different eTextRep parameters and SQLite will use whichever** function requires the least amount of data transformation.** ^If the xCallback argument is NULL then the collating function is** deleted. ^When all collating functions having the same name are deleted,** that collation is no longer usable.**** ^The collating function callback is invoked with a copy of the pArg ** application data pointer and with two strings in the encoding specified** by the eTextRep argument. The collating function must return an** integer that is negative, zero, or positive** if the first string is less than, equal to, or greater than the second,** respectively. A collating function must always return the same answer** given the same inputs. If two or more collating functions are registered** to the same collation name (using different eTextRep values) then all** must give an equivalent answer when invoked with equivalent strings.** The collating function must obey the following properties for all** strings A, B, and C:**** <ol>** <li> If A==B then B==A.** <li> If A==B and B==C then A==C.** <li> If A<B THEN B>A.** <li> If A<B and B<C then A<C.** </ol>**** If a collating function fails any of the above constraints and that** collating function is registered and used, then the behavior of SQLite** is undefined.**** ^The sqlite3_create_collation_v2() works like sqlite3_create_collation()** with the addition that the xDestroy callback is invoked on pArg when** the collating function is deleted.** ^Collating functions are deleted when they are overridden by later** calls to the collation creation functions or when the** [database connection] is closed using [sqlite3_close()].**** ^The xDestroy callback is <u>not</u> called if the ** sqlite3_create_collation_v2() function fails. Applications that invoke** sqlite3_create_collation_v2() with a non-NULL xDestroy argument should ** check the return code and dispose of the application data pointer** themselves rather than expecting SQLite to deal with it for them.** This is different from every other SQLite interface. The inconsistency ** is unfortunate but cannot be changed without breaking backwards ** compatibility.**** See also: [sqlite3_collation_needed()] and [sqlite3_collation_needed16()].*/SQLITE_APIintsqlite3_create_collation(sqlite3*,constchar*zName,inteTextRep,void*pArg,int(*xCompare)(void*,int,constvoid*,int,constvoid*));SQLITE_APIintsqlite3_create_collation_v2(sqlite3*,constchar*zName,inteTextRep,void*pArg,int(*xCompare)(void*,int,constvoid*,int,constvoid*),void(*xDestroy)(void*));SQLITE_APIintsqlite3_create_collation16(sqlite3*,constvoid*zName,inteTextRep,void*pArg,int(*xCompare)(void*,int,constvoid*,int,constvoid*));/*** CAPI3REF: Collation Needed Callbacks** METHOD: sqlite3**** ^To avoid having to register all collation sequences before a database** can be used, a single callback function may be registered with the** [database connection] to be invoked whenever an undefined collation** sequence is required.**** ^If the function is registered using the sqlite3_collation_needed() API,** then it is passed the names of undefined collation sequences as strings** encoded in UTF-8. ^If sqlite3_collation_needed16() is used,** the names are passed as UTF-16 in machine native byte order.** ^A call to either function replaces the existing collation-needed callback.**** ^(When the callback is invoked, the first argument passed is a copy** of the second argument to sqlite3_collation_needed() or** sqlite3_collation_needed16(). The second argument is the database** connection. The third argument is one of [SQLITE_UTF8], [SQLITE_UTF16BE],** or [SQLITE_UTF16LE], indicating the most desirable form of the collation** sequence function required. The fourth parameter is the name of the** required collation sequence.)^**** The callback function should register the desired collation using** [sqlite3_create_collation()], [sqlite3_create_collation16()], or** [sqlite3_create_collation_v2()].*/SQLITE_APIintsqlite3_collation_needed(sqlite3*,void*,void(*)(void*,sqlite3*,inteTextRep,constchar*));SQLITE_APIintsqlite3_collation_needed16(sqlite3*,void*,void(*)(void*,sqlite3*,inteTextRep,constvoid*));#ifdef SQLITE_HAS_CODEC/*** Specify the key for an encrypted database. This routine should be** called right after sqlite3_open().**** The code to implement this API is not available in the public release** of SQLite.*/SQLITE_APIintsqlite3_key(sqlite3*db,/* Database to be rekeyed */constvoid*pKey,intnKey/* The key */);SQLITE_APIintsqlite3_key_v2(sqlite3*db,/* Database to be rekeyed */constchar*zDbName,/* Name of the database */constvoid*pKey,intnKey/* The key */);/*** Change the key on an open database. If the current database is not** encrypted, this routine will encrypt it. If pNew==0 or nNew==0, the** database is decrypted.**** The code to implement this API is not available in the public release** of SQLite.*/SQLITE_APIintsqlite3_rekey(sqlite3*db,/* Database to be rekeyed */constvoid*pKey,intnKey/* The new key */);SQLITE_APIintsqlite3_rekey_v2(sqlite3*db,/* Database to be rekeyed */constchar*zDbName,/* Name of the database */constvoid*pKey,intnKey/* The new key */);/*** Specify the activation key for a SEE database. Unless ** activated, none of the SEE routines will work.*/SQLITE_APIvoidsqlite3_activate_see(constchar*zPassPhrase/* Activation phrase */);#endif#ifdef SQLITE_ENABLE_CEROD/*** Specify the activation key for a CEROD database. Unless ** activated, none of the CEROD routines will work.*/SQLITE_APIvoidsqlite3_activate_cerod(constchar*zPassPhrase/* Activation phrase */);#endif/*** CAPI3REF: Suspend Execution For A Short Time**** The sqlite3_sleep() function causes the current thread to suspend execution** for at least a number of milliseconds specified in its parameter.**** If the operating system does not support sleep requests with** millisecond time resolution, then the time will be rounded up to** the nearest second. The number of milliseconds of sleep actually** requested from the operating system is returned.**** ^SQLite implements this interface by calling the xSleep()** method of the default [sqlite3_vfs] object. If the xSleep() method** of the default VFS is not implemented correctly, or not implemented at** all, then the behavior of sqlite3_sleep() may deviate from the description** in the previous paragraphs.*/SQLITE_APIintsqlite3_sleep(int);/*** CAPI3REF: Name Of The Folder Holding Temporary Files**** ^(If this global variable is made to point to a string which is** the name of a folder (a.k.a. directory), then all temporary files** created by SQLite when using a built-in [sqlite3_vfs | VFS]** will be placed in that directory.)^ ^If this variable** is a NULL pointer, then SQLite performs a search for an appropriate** temporary file directory.**** Applications are strongly discouraged from using this global variable.** It is required to set a temporary folder on Windows Runtime (WinRT).** But for all other platforms, it is highly recommended that applications** neither read nor write this variable. This global variable is a relic** that exists for backwards compatibility of legacy applications and should** be avoided in new projects.**** It is not safe to read or modify this variable in more than one** thread at a time. It is not safe to read or modify this variable** if a [database connection] is being used at the same time in a separate** thread.** It is intended that this variable be set once** as part of process initialization and before any SQLite interface** routines have been called and that this variable remain unchanged** thereafter.**** ^The [temp_store_directory pragma] may modify this variable and cause** it to point to memory obtained from [sqlite3_malloc]. ^Furthermore,** the [temp_store_directory pragma] always assumes that any string** that this variable points to is held in memory obtained from ** [sqlite3_malloc] and the pragma may attempt to free that memory** using [sqlite3_free].** Hence, if this variable is modified directly, either it should be** made NULL or made to point to memory obtained from [sqlite3_malloc]** or else the use of the [temp_store_directory pragma] should be avoided.** Except when requested by the [temp_store_directory pragma], SQLite** does not free the memory that sqlite3_temp_directory points to. If** the application wants that memory to be freed, it must do** so itself, taking care to only do so after all [database connection]** objects have been destroyed.**** <b>Note to Windows Runtime users:</b> The temporary directory must be set** prior to calling [sqlite3_open] or [sqlite3_open_v2]. Otherwise, various** features that require the use of temporary files may fail. Here is an** example of how to do this using C++ with the Windows Runtime:**** <blockquote><pre>** LPCWSTR zPath = Windows::Storage::ApplicationData::Current->** TemporaryFolder->Path->Data();** char zPathBuf[MAX_PATH + 1];** memset(zPathBuf, 0, sizeof(zPathBuf));** WideCharToMultiByte(CP_UTF8, 0, zPath, -1, zPathBuf, sizeof(zPathBuf),** NULL, NULL);** sqlite3_temp_directory = sqlite3_mprintf("%s", zPathBuf);** </pre></blockquote>*/SQLITE_APISQLITE_EXTERNchar*sqlite3_temp_directory;/*** CAPI3REF: Name Of The Folder Holding Database Files**** ^(If this global variable is made to point to a string which is** the name of a folder (a.k.a. directory), then all database files** specified with a relative pathname and created or accessed by** SQLite when using a built-in windows [sqlite3_vfs | VFS] will be assumed** to be relative to that directory.)^ ^If this variable is a NULL** pointer, then SQLite assumes that all database files specified** with a relative pathname are relative to the current directory** for the process. Only the windows VFS makes use of this global** variable; it is ignored by the unix VFS.**** Changing the value of this variable while a database connection is** open can result in a corrupt database.**** It is not safe to read or modify this variable in more than one** thread at a time. It is not safe to read or modify this variable** if a [database connection] is being used at the same time in a separate** thread.** It is intended that this variable be set once** as part of process initialization and before any SQLite interface** routines have been called and that this variable remain unchanged** thereafter.**** ^The [data_store_directory pragma] may modify this variable and cause** it to point to memory obtained from [sqlite3_malloc]. ^Furthermore,** the [data_store_directory pragma] always assumes that any string** that this variable points to is held in memory obtained from ** [sqlite3_malloc] and the pragma may attempt to free that memory** using [sqlite3_free].** Hence, if this variable is modified directly, either it should be** made NULL or made to point to memory obtained from [sqlite3_malloc]** or else the use of the [data_store_directory pragma] should be avoided.*/SQLITE_APISQLITE_EXTERNchar*sqlite3_data_directory;/*** CAPI3REF: Test For Auto-Commit Mode** KEYWORDS: {autocommit mode}** METHOD: sqlite3**** ^The sqlite3_get_autocommit() interface returns non-zero or** zero if the given database connection is or is not in autocommit mode,** respectively. ^Autocommit mode is on by default.** ^Autocommit mode is disabled by a [BEGIN] statement.** ^Autocommit mode is re-enabled by a [COMMIT] or [ROLLBACK].**** If certain kinds of errors occur on a statement within a multi-statement** transaction (errors including [SQLITE_FULL], [SQLITE_IOERR],** [SQLITE_NOMEM], [SQLITE_BUSY], and [SQLITE_INTERRUPT]) then the** transaction might be rolled back automatically. The only way to** find out whether SQLite automatically rolled back the transaction after** an error is to use this function.**** If another thread changes the autocommit status of the database** connection while this routine is running, then the return value** is undefined.*/SQLITE_APIintsqlite3_get_autocommit(sqlite3*);/*** CAPI3REF: Find The Database Handle Of A Prepared Statement** METHOD: sqlite3_stmt**** ^The sqlite3_db_handle interface returns the [database connection] handle** to which a [prepared statement] belongs. ^The [database connection]** returned by sqlite3_db_handle is the same [database connection]** that was the first argument** to the [sqlite3_prepare_v2()] call (or its variants) that was used to** create the statement in the first place.*/SQLITE_APIsqlite3*sqlite3_db_handle(sqlite3_stmt*);/*** CAPI3REF: Return The Filename For A Database Connection** METHOD: sqlite3**** ^The sqlite3_db_filename(D,N) interface returns a pointer to a filename** associated with database N of connection D. ^The main database file** has the name "main". If there is no attached database N on the database** connection D, or if database N is a temporary or in-memory database, then** a NULL pointer is returned.**** ^The filename returned by this function is the output of the** xFullPathname method of the [VFS]. ^In other words, the filename** will be an absolute pathname, even if the filename used** to open the database originally was a URI or relative pathname.*/SQLITE_APIconstchar*sqlite3_db_filename(sqlite3*db,constchar*zDbName);/*** CAPI3REF: Determine if a database is read-only** METHOD: sqlite3**** ^The sqlite3_db_readonly(D,N) interface returns 1 if the database N** of connection D is read-only, 0 if it is read/write, or -1 if N is not** the name of a database on connection D.*/SQLITE_APIintsqlite3_db_readonly(sqlite3*db,constchar*zDbName);/*** CAPI3REF: Find the next prepared statement** METHOD: sqlite3**** ^This interface returns a pointer to the next [prepared statement] after** pStmt associated with the [database connection] pDb. ^If pStmt is NULL** then this interface returns a pointer to the first prepared statement** associated with the database connection pDb. ^If no prepared statement** satisfies the conditions of this routine, it returns NULL.**** The [database connection] pointer D in a call to** [sqlite3_next_stmt(D,S)] must refer to an open database** connection and in particular must not be a NULL pointer.*/SQLITE_APIsqlite3_stmt*sqlite3_next_stmt(sqlite3*pDb,sqlite3_stmt*pStmt);/*** CAPI3REF: Commit And Rollback Notification Callbacks** METHOD: sqlite3**** ^The sqlite3_commit_hook() interface registers a callback** function to be invoked whenever a transaction is [COMMIT | committed].** ^Any callback set by a previous call to sqlite3_commit_hook()** for the same database connection is overridden.** ^The sqlite3_rollback_hook() interface registers a callback** function to be invoked whenever a transaction is [ROLLBACK | rolled back].** ^Any callback set by a previous call to sqlite3_rollback_hook()** for the same database connection is overridden.** ^The pArg argument is passed through to the callback.** ^If the callback on a commit hook function returns non-zero,** then the commit is converted into a rollback.**** ^The sqlite3_commit_hook(D,C,P) and sqlite3_rollback_hook(D,C,P) functions** return the P argument from the previous call of the same function** on the same [database connection] D, or NULL for** the first call for each function on D.**** The commit and rollback hook callbacks are not reentrant.** The callback implementation must not do anything that will modify** the database connection that invoked the callback. Any actions** to modify the database connection must be deferred until after the** completion of the [sqlite3_step()] call that triggered the commit** or rollback hook in the first place.** Note that running any other SQL statements, including SELECT statements,** or merely calling [sqlite3_prepare_v2()] and [sqlite3_step()] will modify** the database connections for the meaning of "modify" in this paragraph.**** ^Registering a NULL function disables the callback.**** ^When the commit hook callback routine returns zero, the [COMMIT]** operation is allowed to continue normally. ^If the commit hook** returns non-zero, then the [COMMIT] is converted into a [ROLLBACK].** ^The rollback hook is invoked on a rollback that results from a commit** hook returning non-zero, just as it would be with any other rollback.**** ^For the purposes of this API, a transaction is said to have been** rolled back if an explicit "ROLLBACK" statement is executed, or** an error or constraint causes an implicit rollback to occur.** ^The rollback callback is not invoked if a transaction is** automatically rolled back because the database connection is closed.**** See also the [sqlite3_update_hook()] interface.*/SQLITE_APIvoid*sqlite3_commit_hook(sqlite3*,int(*)(void*),void*);SQLITE_APIvoid*sqlite3_rollback_hook(sqlite3*,void(*)(void*),void*);/*** CAPI3REF: Data Change Notification Callbacks** METHOD: sqlite3**** ^The sqlite3_update_hook() interface registers a callback function** with the [database connection] identified by the first argument** to be invoked whenever a row is updated, inserted or deleted in** a [rowid table].** ^Any callback set by a previous call to this function** for the same database connection is overridden.**** ^The second argument is a pointer to the function to invoke when a** row is updated, inserted or deleted in a rowid table.** ^The first argument to the callback is a copy of the third argument** to sqlite3_update_hook().** ^The second callback argument is one of [SQLITE_INSERT], [SQLITE_DELETE],** or [SQLITE_UPDATE], depending on the operation that caused the callback** to be invoked.** ^The third and fourth arguments to the callback contain pointers to the** database and table name containing the affected row.** ^The final callback parameter is the [rowid] of the row.** ^In the case of an update, this is the [rowid] after the update takes place.**** ^(The update hook is not invoked when internal system tables are** modified (i.e. sqlite_master and sqlite_sequence).)^** ^The update hook is not invoked when [WITHOUT ROWID] tables are modified.**** ^In the current implementation, the update hook** is not invoked when duplication rows are deleted because of an** [ON CONFLICT | ON CONFLICT REPLACE] clause. ^Nor is the update hook** invoked when rows are deleted using the [truncate optimization].** The exceptions defined in this paragraph might change in a future** release of SQLite.**** The update hook implementation must not do anything that will modify** the database connection that invoked the update hook. Any actions** to modify the database connection must be deferred until after the** completion of the [sqlite3_step()] call that triggered the update hook.** Note that [sqlite3_prepare_v2()] and [sqlite3_step()] both modify their** database connections for the meaning of "modify" in this paragraph.**** ^The sqlite3_update_hook(D,C,P) function** returns the P argument from the previous call** on the same [database connection] D, or NULL for** the first call on D.**** See also the [sqlite3_commit_hook()], [sqlite3_rollback_hook()],** and [sqlite3_preupdate_hook()] interfaces.*/SQLITE_APIvoid*sqlite3_update_hook(sqlite3*,void(*)(void*,int,charconst*,charconst*,sqlite3_int64),void*);/*** CAPI3REF: Enable Or Disable Shared Pager Cache**** ^(This routine enables or disables the sharing of the database cache** and schema data structures between [database connection | connections]** to the same database. Sharing is enabled if the argument is true** and disabled if the argument is false.)^**** ^Cache sharing is enabled and disabled for an entire process.** This is a change as of SQLite [version 3.5.0] ([dateof:3.5.0]). ** In prior versions of SQLite,** sharing was enabled or disabled for each thread separately.**** ^(The cache sharing mode set by this interface effects all subsequent** calls to [sqlite3_open()], [sqlite3_open_v2()], and [sqlite3_open16()].** Existing database connections continue use the sharing mode** that was in effect at the time they were opened.)^**** ^(This routine returns [SQLITE_OK] if shared cache was enabled or disabled** successfully. An [error code] is returned otherwise.)^**** ^Shared cache is disabled by default. But this might change in** future releases of SQLite. Applications that care about shared** cache setting should set it explicitly.**** Note: This method is disabled on MacOS X 10.7 and iOS version 5.0** and will always return SQLITE_MISUSE. On those systems, ** shared cache mode should be enabled per-database connection via ** [sqlite3_open_v2()] with [SQLITE_OPEN_SHAREDCACHE].**** This interface is threadsafe on processors where writing a** 32-bit integer is atomic.**** See Also: [SQLite Shared-Cache Mode]*/SQLITE_APIintsqlite3_enable_shared_cache(int);/*** CAPI3REF: Attempt To Free Heap Memory**** ^The sqlite3_release_memory() interface attempts to free N bytes** of heap memory by deallocating non-essential memory allocations** held by the database library. Memory used to cache database** pages to improve performance is an example of non-essential memory.** ^sqlite3_release_memory() returns the number of bytes actually freed,** which might be more or less than the amount requested.** ^The sqlite3_release_memory() routine is a no-op returning zero** if SQLite is not compiled with [SQLITE_ENABLE_MEMORY_MANAGEMENT].**** See also: [sqlite3_db_release_memory()]*/SQLITE_APIintsqlite3_release_memory(int);/*** CAPI3REF: Free Memory Used By A Database Connection** METHOD: sqlite3**** ^The sqlite3_db_release_memory(D) interface attempts to free as much heap** memory as possible from database connection D. Unlike the** [sqlite3_release_memory()] interface, this interface is in effect even** when the [SQLITE_ENABLE_MEMORY_MANAGEMENT] compile-time option is** omitted.**** See also: [sqlite3_release_memory()]*/SQLITE_APIintsqlite3_db_release_memory(sqlite3*);/*** CAPI3REF: Impose A Limit On Heap Size**** ^The sqlite3_soft_heap_limit64() interface sets and/or queries the** soft limit on the amount of heap memory that may be allocated by SQLite.** ^SQLite strives to keep heap memory utilization below the soft heap** limit by reducing the number of pages held in the page cache** as heap memory usages approaches the limit.** ^The soft heap limit is "soft" because even though SQLite strives to stay** below the limit, it will exceed the limit rather than generate** an [SQLITE_NOMEM] error. In other words, the soft heap limit ** is advisory only.**** ^The return value from sqlite3_soft_heap_limit64() is the size of** the soft heap limit prior to the call, or negative in the case of an** error. ^If the argument N is negative** then no change is made to the soft heap limit. Hence, the current** size of the soft heap limit can be determined by invoking** sqlite3_soft_heap_limit64() with a negative argument.**** ^If the argument N is zero then the soft heap limit is disabled.**** ^(The soft heap limit is not enforced in the current implementation** if one or more of following conditions are true:**** <ul>** <li> The soft heap limit is set to zero.** <li> Memory accounting is disabled using a combination of the** [sqlite3_config]([SQLITE_CONFIG_MEMSTATUS],...) start-time option and** the [SQLITE_DEFAULT_MEMSTATUS] compile-time option.** <li> An alternative page cache implementation is specified using** [sqlite3_config]([SQLITE_CONFIG_PCACHE2],...).** <li> The page cache allocates from its own memory pool supplied** by [sqlite3_config]([SQLITE_CONFIG_PAGECACHE],...) rather than** from the heap.** </ul>)^**** Beginning with SQLite [version 3.7.3] ([dateof:3.7.3]), ** the soft heap limit is enforced** regardless of whether or not the [SQLITE_ENABLE_MEMORY_MANAGEMENT]** compile-time option is invoked. With [SQLITE_ENABLE_MEMORY_MANAGEMENT],** the soft heap limit is enforced on every memory allocation. Without** [SQLITE_ENABLE_MEMORY_MANAGEMENT], the soft heap limit is only enforced** when memory is allocated by the page cache. Testing suggests that because** the page cache is the predominate memory user in SQLite, most** applications will achieve adequate soft heap limit enforcement without** the use of [SQLITE_ENABLE_MEMORY_MANAGEMENT].**** The circumstances under which SQLite will enforce the soft heap limit may** changes in future releases of SQLite.*/SQLITE_APIsqlite3_int64sqlite3_soft_heap_limit64(sqlite3_int64N);/*** CAPI3REF: Deprecated Soft Heap Limit Interface** DEPRECATED**** This is a deprecated version of the [sqlite3_soft_heap_limit64()]** interface. This routine is provided for historical compatibility** only. All new applications should use the** [sqlite3_soft_heap_limit64()] interface rather than this one.*/SQLITE_APISQLITE_DEPRECATEDvoidsqlite3_soft_heap_limit(intN);/*** CAPI3REF: Extract Metadata About A Column Of A Table** METHOD: sqlite3**** ^(The sqlite3_table_column_metadata(X,D,T,C,....) routine returns** information about column C of table T in database D** on [database connection] X.)^ ^The sqlite3_table_column_metadata()** interface returns SQLITE_OK and fills in the non-NULL pointers in** the final five arguments with appropriate values if the specified** column exists. ^The sqlite3_table_column_metadata() interface returns** SQLITE_ERROR and if the specified column does not exist.** ^If the column-name parameter to sqlite3_table_column_metadata() is a** NULL pointer, then this routine simply checks for the existence of the** table and returns SQLITE_OK if the table exists and SQLITE_ERROR if it** does not.**** ^The column is identified by the second, third and fourth parameters to** this function. ^(The second parameter is either the name of the database** (i.e. "main", "temp", or an attached database) containing the specified** table or NULL.)^ ^If it is NULL, then all attached databases are searched** for the table using the same algorithm used by the database engine to** resolve unqualified table references.**** ^The third and fourth parameters to this function are the table and column** name of the desired column, respectively.**** ^Metadata is returned by writing to the memory locations passed as the 5th** and subsequent parameters to this function. ^Any of these arguments may be** NULL, in which case the corresponding element of metadata is omitted.**** ^(<blockquote>** <table border="1">** <tr><th> Parameter <th> Output<br>Type <th> Description**** <tr><td> 5th <td> const char* <td> Data type** <tr><td> 6th <td> const char* <td> Name of default collation sequence** <tr><td> 7th <td> int <td> True if column has a NOT NULL constraint** <tr><td> 8th <td> int <td> True if column is part of the PRIMARY KEY** <tr><td> 9th <td> int <td> True if column is [AUTOINCREMENT]** </table>** </blockquote>)^**** ^The memory pointed to by the character pointers returned for the** declaration type and collation sequence is valid until the next** call to any SQLite API function.**** ^If the specified table is actually a view, an [error code] is returned.**** ^If the specified column is "rowid", "oid" or "_rowid_" and the table ** is not a [WITHOUT ROWID] table and an** [INTEGER PRIMARY KEY] column has been explicitly declared, then the output** parameters are set for the explicitly declared column. ^(If there is no** [INTEGER PRIMARY KEY] column, then the outputs** for the [rowid] are set as follows:**** <pre>** data type: "INTEGER"** collation sequence: "BINARY"** not null: 0** primary key: 1** auto increment: 0** </pre>)^**** ^This function causes all database schemas to be read from disk and** parsed, if that has not already been done, and returns an error if** any errors are encountered while loading the schema.*/SQLITE_APIintsqlite3_table_column_metadata(sqlite3*db,/* Connection handle */constchar*zDbName,/* Database name or NULL */constchar*zTableName,/* Table name */constchar*zColumnName,/* Column name */charconst**pzDataType,/* OUTPUT: Declared data type */charconst**pzCollSeq,/* OUTPUT: Collation sequence name */int*pNotNull,/* OUTPUT: True if NOT NULL constraint exists */int*pPrimaryKey,/* OUTPUT: True if column part of PK */int*pAutoinc/* OUTPUT: True if column is auto-increment */);/*** CAPI3REF: Load An Extension** METHOD: sqlite3**** ^This interface loads an SQLite extension library from the named file.**** ^The sqlite3_load_extension() interface attempts to load an** [SQLite extension] library contained in the file zFile. If** the file cannot be loaded directly, attempts are made to load** with various operating-system specific extensions added.** So for example, if "samplelib" cannot be loaded, then names like** "samplelib.so" or "samplelib.dylib" or "samplelib.dll" might** be tried also.**** ^The entry point is zProc.** ^(zProc may be 0, in which case SQLite will try to come up with an** entry point name on its own. It first tries "sqlite3_extension_init".** If that does not work, it constructs a name "sqlite3_X_init" where the** X is consists of the lower-case equivalent of all ASCII alphabetic** characters in the filename from the last "/" to the first following** "." and omitting any initial "lib".)^** ^The sqlite3_load_extension() interface returns** [SQLITE_OK] on success and [SQLITE_ERROR] if something goes wrong.** ^If an error occurs and pzErrMsg is not 0, then the** [sqlite3_load_extension()] interface shall attempt to** fill *pzErrMsg with error message text stored in memory** obtained from [sqlite3_malloc()]. The calling function** should free this memory by calling [sqlite3_free()].**** ^Extension loading must be enabled using** [sqlite3_enable_load_extension()] or** [sqlite3_db_config](db,[SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION],1,NULL)** prior to calling this API,** otherwise an error will be returned.**** <b>Security warning:</b> It is recommended that the ** [SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION] method be used to enable only this** interface. The use of the [sqlite3_enable_load_extension()] interface** should be avoided. This will keep the SQL function [load_extension()]** disabled and prevent SQL injections from giving attackers** access to extension loading capabilities.**** See also the [load_extension() SQL function].*/SQLITE_APIintsqlite3_load_extension(sqlite3*db,/* Load the extension into this database connection */constchar*zFile,/* Name of the shared library containing extension */constchar*zProc,/* Entry point. Derived from zFile if 0 */char**pzErrMsg/* Put error message here if not 0 */);/*** CAPI3REF: Enable Or Disable Extension Loading** METHOD: sqlite3**** ^So as not to open security holes in older applications that are** unprepared to deal with [extension loading], and as a means of disabling** [extension loading] while evaluating user-entered SQL, the following API** is provided to turn the [sqlite3_load_extension()] mechanism on and off.**** ^Extension loading is off by default.** ^Call the sqlite3_enable_load_extension() routine with onoff==1** to turn extension loading on and call it with onoff==0 to turn** it back off again.**** ^This interface enables or disables both the C-API** [sqlite3_load_extension()] and the SQL function [load_extension()].** ^(Use [sqlite3_db_config](db,[SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION],..)** to enable or disable only the C-API.)^**** <b>Security warning:</b> It is recommended that extension loading** be disabled using the [SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION] method** rather than this interface, so the [load_extension()] SQL function** remains disabled. This will prevent SQL injections from giving attackers** access to extension loading capabilities.*/SQLITE_APIintsqlite3_enable_load_extension(sqlite3*db,intonoff);/*** CAPI3REF: Automatically Load Statically Linked Extensions**** ^This interface causes the xEntryPoint() function to be invoked for** each new [database connection] that is created. The idea here is that** xEntryPoint() is the entry point for a statically linked [SQLite extension]** that is to be automatically loaded into all new database connections.**** ^(Even though the function prototype shows that xEntryPoint() takes** no arguments and returns void, SQLite invokes xEntryPoint() with three** arguments and expects an integer result as if the signature of the** entry point where as follows:**** <blockquote><pre>** int xEntryPoint(** sqlite3 *db,** const char **pzErrMsg,** const struct sqlite3_api_routines *pThunk** );** </pre></blockquote>)^**** If the xEntryPoint routine encounters an error, it should make *pzErrMsg** point to an appropriate error message (obtained from [sqlite3_mprintf()])** and return an appropriate [error code]. ^SQLite ensures that *pzErrMsg** is NULL before calling the xEntryPoint(). ^SQLite will invoke** [sqlite3_free()] on *pzErrMsg after xEntryPoint() returns. ^If any** xEntryPoint() returns an error, the [sqlite3_open()], [sqlite3_open16()],** or [sqlite3_open_v2()] call that provoked the xEntryPoint() will fail.**** ^Calling sqlite3_auto_extension(X) with an entry point X that is already** on the list of automatic extensions is a harmless no-op. ^No entry point** will be called more than once for each database connection that is opened.**** See also: [sqlite3_reset_auto_extension()]** and [sqlite3_cancel_auto_extension()]*/SQLITE_APIintsqlite3_auto_extension(void(*xEntryPoint)(void));/*** CAPI3REF: Cancel Automatic Extension Loading**** ^The [sqlite3_cancel_auto_extension(X)] interface unregisters the** initialization routine X that was registered using a prior call to** [sqlite3_auto_extension(X)]. ^The [sqlite3_cancel_auto_extension(X)]** routine returns 1 if initialization routine X was successfully ** unregistered and it returns 0 if X was not on the list of initialization** routines.*/SQLITE_APIintsqlite3_cancel_auto_extension(void(*xEntryPoint)(void));/*** CAPI3REF: Reset Automatic Extension Loading**** ^This interface disables all automatic extensions previously** registered using [sqlite3_auto_extension()].*/SQLITE_APIvoidsqlite3_reset_auto_extension(void);/*** The interface to the virtual-table mechanism is currently considered** to be experimental. The interface might change in incompatible ways.** If this is a problem for you, do not use the interface at this time.**** When the virtual-table mechanism stabilizes, we will declare the** interface fixed, support it indefinitely, and remove this comment.*//*** Structures used by the virtual table interface*/typedefstructsqlite3_vtabsqlite3_vtab;typedefstructsqlite3_index_infosqlite3_index_info;typedefstructsqlite3_vtab_cursorsqlite3_vtab_cursor;typedefstructsqlite3_modulesqlite3_module;/*** CAPI3REF: Virtual Table Object** KEYWORDS: sqlite3_module {virtual table module}**** This structure, sometimes called a "virtual table module", ** defines the implementation of a [virtual tables]. ** This structure consists mostly of methods for the module.**** ^A virtual table module is created by filling in a persistent** instance of this structure and passing a pointer to that instance** to [sqlite3_create_module()] or [sqlite3_create_module_v2()].** ^The registration remains valid until it is replaced by a different** module or until the [database connection] closes. The content** of this structure must not change while it is registered with** any database connection.*/structsqlite3_module{intiVersion;int(*xCreate)(sqlite3*,void*pAux,intargc,constchar*const*argv,sqlite3_vtab**ppVTab,char**);int(*xConnect)(sqlite3*,void*pAux,intargc,constchar*const*argv,sqlite3_vtab**ppVTab,char**);int(*xBestIndex)(sqlite3_vtab*pVTab,sqlite3_index_info*);int(*xDisconnect)(sqlite3_vtab*pVTab);int(*xDestroy)(sqlite3_vtab*pVTab);int(*xOpen)(sqlite3_vtab*pVTab,sqlite3_vtab_cursor**ppCursor);int(*xClose)(sqlite3_vtab_cursor*);int(*xFilter)(sqlite3_vtab_cursor*,intidxNum,constchar*idxStr,intargc,sqlite3_value**argv);int(*xNext)(sqlite3_vtab_cursor*);int(*xEof)(sqlite3_vtab_cursor*);int(*xColumn)(sqlite3_vtab_cursor*,sqlite3_context*,int);int(*xRowid)(sqlite3_vtab_cursor*,sqlite3_int64*pRowid);int(*xUpdate)(sqlite3_vtab*,int,sqlite3_value**,sqlite3_int64*);int(*xBegin)(sqlite3_vtab*pVTab);int(*xSync)(sqlite3_vtab*pVTab);int(*xCommit)(sqlite3_vtab*pVTab);int(*xRollback)(sqlite3_vtab*pVTab);int(*xFindFunction)(sqlite3_vtab*pVtab,intnArg,constchar*zName,void(**pxFunc)(sqlite3_context*,int,sqlite3_value**),void**ppArg);int(*xRename)(sqlite3_vtab*pVtab,constchar*zNew);/* The methods above are in version 1 of the sqlite_module object. Those ** below are for version 2 and greater. */int(*xSavepoint)(sqlite3_vtab*pVTab,int);int(*xRelease)(sqlite3_vtab*pVTab,int);int(*xRollbackTo)(sqlite3_vtab*pVTab,int);};/*** CAPI3REF: Virtual Table Indexing Information** KEYWORDS: sqlite3_index_info**** The sqlite3_index_info structure and its substructures is used as part** of the [virtual table] interface to** pass information into and receive the reply from the [xBestIndex]** method of a [virtual table module]. The fields under **Inputs** are the** inputs to xBestIndex and are read-only. xBestIndex inserts its** results into the **Outputs** fields.**** ^(The aConstraint[] array records WHERE clause constraints of the form:**** <blockquote>column OP expr</blockquote>**** where OP is =, <, <=, >, or >=.)^ ^(The particular operator is** stored in aConstraint[].op using one of the** [SQLITE_INDEX_CONSTRAINT_EQ | SQLITE_INDEX_CONSTRAINT_ values].)^** ^(The index of the column is stored in** aConstraint[].iColumn.)^ ^(aConstraint[].usable is TRUE if the** expr on the right-hand side can be evaluated (and thus the constraint** is usable) and false if it cannot.)^**** ^The optimizer automatically inverts terms of the form "expr OP column"** and makes other simplifications to the WHERE clause in an attempt to** get as many WHERE clause terms into the form shown above as possible.** ^The aConstraint[] array only reports WHERE clause terms that are** relevant to the particular virtual table being queried.**** ^Information about the ORDER BY clause is stored in aOrderBy[].** ^Each term of aOrderBy records a column of the ORDER BY clause.**** The colUsed field indicates which columns of the virtual table may be** required by the current scan. Virtual table columns are numbered from** zero in the order in which they appear within the CREATE TABLE statement** passed to sqlite3_declare_vtab(). For the first 63 columns (columns 0-62),** the corresponding bit is set within the colUsed mask if the column may be** required by SQLite. If the table has at least 64 columns and any column** to the right of the first 63 is required, then bit 63 of colUsed is also** set. In other words, column iCol may be required if the expression** (colUsed & ((sqlite3_uint64)1 << (iCol>=63 ? 63 : iCol))) evaluates to ** non-zero.**** The [xBestIndex] method must fill aConstraintUsage[] with information** about what parameters to pass to xFilter. ^If argvIndex>0 then** the right-hand side of the corresponding aConstraint[] is evaluated** and becomes the argvIndex-th entry in argv. ^(If aConstraintUsage[].omit** is true, then the constraint is assumed to be fully handled by the** virtual table and is not checked again by SQLite.)^**** ^The idxNum and idxPtr values are recorded and passed into the** [xFilter] method.** ^[sqlite3_free()] is used to free idxPtr if and only if** needToFreeIdxPtr is true.**** ^The orderByConsumed means that output from [xFilter]/[xNext] will occur in** the correct order to satisfy the ORDER BY clause so that no separate** sorting step is required.**** ^The estimatedCost value is an estimate of the cost of a particular** strategy. A cost of N indicates that the cost of the strategy is similar** to a linear scan of an SQLite table with N rows. A cost of log(N) ** indicates that the expense of the operation is similar to that of a** binary search on a unique indexed field of an SQLite table with N rows.**** ^The estimatedRows value is an estimate of the number of rows that** will be returned by the strategy.**** The xBestIndex method may optionally populate the idxFlags field with a ** mask of SQLITE_INDEX_SCAN_* flags. Currently there is only one such flag -** SQLITE_INDEX_SCAN_UNIQUE. If the xBestIndex method sets this flag, SQLite** assumes that the strategy may visit at most one row. **** Additionally, if xBestIndex sets the SQLITE_INDEX_SCAN_UNIQUE flag, then** SQLite also assumes that if a call to the xUpdate() method is made as** part of the same statement to delete or update a virtual table row and the** implementation returns SQLITE_CONSTRAINT, then there is no need to rollback** any database changes. In other words, if the xUpdate() returns** SQLITE_CONSTRAINT, the database contents must be exactly as they were** before xUpdate was called. By contrast, if SQLITE_INDEX_SCAN_UNIQUE is not** set and xUpdate returns SQLITE_CONSTRAINT, any database changes made by** the xUpdate method are automatically rolled back by SQLite.**** IMPORTANT: The estimatedRows field was added to the sqlite3_index_info** structure for SQLite [version 3.8.2] ([dateof:3.8.2]). ** If a virtual table extension is** used with an SQLite version earlier than 3.8.2, the results of attempting ** to read or write the estimatedRows field are undefined (but are likely ** to included crashing the application). The estimatedRows field should** therefore only be used if [sqlite3_libversion_number()] returns a** value greater than or equal to 3008002. Similarly, the idxFlags field** was added for [version 3.9.0] ([dateof:3.9.0]). ** It may therefore only be used if** sqlite3_libversion_number() returns a value greater than or equal to** 3009000.*/structsqlite3_index_info{/* Inputs */intnConstraint;/* Number of entries in aConstraint */structsqlite3_index_constraint{intiColumn;/* Column constrained. -1 for ROWID */unsignedcharop;/* Constraint operator */unsignedcharusable;/* True if this constraint is usable */intiTermOffset;/* Used internally - xBestIndex should ignore */}*aConstraint;/* Table of WHERE clause constraints */intnOrderBy;/* Number of terms in the ORDER BY clause */structsqlite3_index_orderby{intiColumn;/* Column number */unsignedchardesc;/* True for DESC. False for ASC. */}*aOrderBy;/* The ORDER BY clause *//* Outputs */structsqlite3_index_constraint_usage{intargvIndex;/* if >0, constraint is part of argv to xFilter */unsignedcharomit;/* Do not code a test for this constraint */}*aConstraintUsage;intidxNum;/* Number used to identify the index */char*idxStr;/* String, possibly obtained from sqlite3_malloc */intneedToFreeIdxStr;/* Free idxStr using sqlite3_free() if true */intorderByConsumed;/* True if output is already ordered */doubleestimatedCost;/* Estimated cost of using this index *//* Fields below are only available in SQLite 3.8.2 and later */sqlite3_int64estimatedRows;/* Estimated number of rows returned *//* Fields below are only available in SQLite 3.9.0 and later */intidxFlags;/* Mask of SQLITE_INDEX_SCAN_* flags *//* Fields below are only available in SQLite 3.10.0 and later */sqlite3_uint64colUsed;/* Input: Mask of columns used by statement */};/*** CAPI3REF: Virtual Table Scan Flags*/#define SQLITE_INDEX_SCAN_UNIQUE 1 /* Scan visits at most 1 row *//*** CAPI3REF: Virtual Table Constraint Operator Codes**** These macros defined the allowed values for the** [sqlite3_index_info].aConstraint[].op field. Each value represents** an operator that is part of a constraint term in the wHERE clause of** a query that uses a [virtual table].*/#define SQLITE_INDEX_CONSTRAINT_EQ 2#define SQLITE_INDEX_CONSTRAINT_GT 4#define SQLITE_INDEX_CONSTRAINT_LE 8#define SQLITE_INDEX_CONSTRAINT_LT 16#define SQLITE_INDEX_CONSTRAINT_GE 32#define SQLITE_INDEX_CONSTRAINT_MATCH 64#define SQLITE_INDEX_CONSTRAINT_LIKE 65#define SQLITE_INDEX_CONSTRAINT_GLOB 66#define SQLITE_INDEX_CONSTRAINT_REGEXP 67/*** CAPI3REF: Register A Virtual Table Implementation** METHOD: sqlite3**** ^These routines are used to register a new [virtual table module] name.** ^Module names must be registered before** creating a new [virtual table] using the module and before using a** preexisting [virtual table] for the module.**** ^The module name is registered on the [database connection] specified** by the first parameter. ^The name of the module is given by the ** second parameter. ^The third parameter is a pointer to** the implementation of the [virtual table module]. ^The fourth** parameter is an arbitrary client data pointer that is passed through** into the [xCreate] and [xConnect] methods of the virtual table module** when a new virtual table is be being created or reinitialized.**** ^The sqlite3_create_module_v2() interface has a fifth parameter which** is a pointer to a destructor for the pClientData. ^SQLite will** invoke the destructor function (if it is not NULL) when SQLite** no longer needs the pClientData pointer. ^The destructor will also** be invoked if the call to sqlite3_create_module_v2() fails.** ^The sqlite3_create_module()** interface is equivalent to sqlite3_create_module_v2() with a NULL** destructor.*/SQLITE_APIintsqlite3_create_module(sqlite3*db,/* SQLite connection to register module with */constchar*zName,/* Name of the module */constsqlite3_module*p,/* Methods for the module */void*pClientData/* Client data for xCreate/xConnect */);SQLITE_APIintsqlite3_create_module_v2(sqlite3*db,/* SQLite connection to register module with */constchar*zName,/* Name of the module */constsqlite3_module*p,/* Methods for the module */void*pClientData,/* Client data for xCreate/xConnect */void(*xDestroy)(void*)/* Module destructor function */);/*** CAPI3REF: Virtual Table Instance Object** KEYWORDS: sqlite3_vtab**** Every [virtual table module] implementation uses a subclass** of this object to describe a particular instance** of the [virtual table]. Each subclass will** be tailored to the specific needs of the module implementation.** The purpose of this superclass is to define certain fields that are** common to all module implementations.**** ^Virtual tables methods can set an error message by assigning a** string obtained from [sqlite3_mprintf()] to zErrMsg. The method should** take care that any prior string is freed by a call to [sqlite3_free()]** prior to assigning a new string to zErrMsg. ^After the error message** is delivered up to the client application, the string will be automatically** freed by sqlite3_free() and the zErrMsg field will be zeroed.*/structsqlite3_vtab{constsqlite3_module*pModule;/* The module for this virtual table */intnRef;/* Number of open cursors */char*zErrMsg;/* Error message from sqlite3_mprintf() *//* Virtual table implementations will typically add additional fields */};/*** CAPI3REF: Virtual Table Cursor Object** KEYWORDS: sqlite3_vtab_cursor {virtual table cursor}**** Every [virtual table module] implementation uses a subclass of the** following structure to describe cursors that point into the** [virtual table] and are used** to loop through the virtual table. Cursors are created using the** [sqlite3_module.xOpen | xOpen] method of the module and are destroyed** by the [sqlite3_module.xClose | xClose] method. Cursors are used** by the [xFilter], [xNext], [xEof], [xColumn], and [xRowid] methods** of the module. Each module implementation will define** the content of a cursor structure to suit its own needs.**** This superclass exists in order to define fields of the cursor that** are common to all implementations.*/structsqlite3_vtab_cursor{sqlite3_vtab*pVtab;/* Virtual table of this cursor *//* Virtual table implementations will typically add additional fields */};/*** CAPI3REF: Declare The Schema Of A Virtual Table**** ^The [xCreate] and [xConnect] methods of a** [virtual table module] call this interface** to declare the format (the names and datatypes of the columns) of** the virtual tables they implement.*/SQLITE_APIintsqlite3_declare_vtab(sqlite3*,constchar*zSQL);/*** CAPI3REF: Overload A Function For A Virtual Table** METHOD: sqlite3**** ^(Virtual tables can provide alternative implementations of functions** using the [xFindFunction] method of the [virtual table module]. ** But global versions of those functions** must exist in order to be overloaded.)^**** ^(This API makes sure a global version of a function with a particular** name and number of parameters exists. If no such function exists** before this API is called, a new function is created.)^ ^The implementation** of the new function always causes an exception to be thrown. So** the new function is not good for anything by itself. Its only** purpose is to be a placeholder function that can be overloaded** by a [virtual table].*/SQLITE_APIintsqlite3_overload_function(sqlite3*,constchar*zFuncName,intnArg);/*** The interface to the virtual-table mechanism defined above (back up** to a comment remarkably similar to this one) is currently considered** to be experimental. The interface might change in incompatible ways.** If this is a problem for you, do not use the interface at this time.**** When the virtual-table mechanism stabilizes, we will declare the** interface fixed, support it indefinitely, and remove this comment.*//*** CAPI3REF: A Handle To An Open BLOB** KEYWORDS: {BLOB handle} {BLOB handles}**** An instance of this object represents an open BLOB on which** [sqlite3_blob_open | incremental BLOB I/O] can be performed.** ^Objects of this type are created by [sqlite3_blob_open()]** and destroyed by [sqlite3_blob_close()].** ^The [sqlite3_blob_read()] and [sqlite3_blob_write()] interfaces** can be used to read or write small subsections of the BLOB.** ^The [sqlite3_blob_bytes()] interface returns the size of the BLOB in bytes.*/typedefstructsqlite3_blobsqlite3_blob;/*** CAPI3REF: Open A BLOB For Incremental I/O** METHOD: sqlite3** CONSTRUCTOR: sqlite3_blob**** ^(This interfaces opens a [BLOB handle | handle] to the BLOB located** in row iRow, column zColumn, table zTable in database zDb;** in other words, the same BLOB that would be selected by:**** <pre>** SELECT zColumn FROM zDb.zTable WHERE [rowid] = iRow;** </pre>)^**** ^(Parameter zDb is not the filename that contains the database, but ** rather the symbolic name of the database. For attached databases, this is** the name that appears after the AS keyword in the [ATTACH] statement.** For the main database file, the database name is "main". For TEMP** tables, the database name is "temp".)^**** ^If the flags parameter is non-zero, then the BLOB is opened for read** and write access. ^If the flags parameter is zero, the BLOB is opened for** read-only access.**** ^(On success, [SQLITE_OK] is returned and the new [BLOB handle] is stored** in *ppBlob. Otherwise an [error code] is returned and, unless the error** code is SQLITE_MISUSE, *ppBlob is set to NULL.)^ ^This means that, provided** the API is not misused, it is always safe to call [sqlite3_blob_close()] ** on *ppBlob after this function it returns.**** This function fails with SQLITE_ERROR if any of the following are true:** <ul>** <li> ^(Database zDb does not exist)^, ** <li> ^(Table zTable does not exist within database zDb)^, ** <li> ^(Table zTable is a WITHOUT ROWID table)^, ** <li> ^(Column zColumn does not exist)^,** <li> ^(Row iRow is not present in the table)^,** <li> ^(The specified column of row iRow contains a value that is not** a TEXT or BLOB value)^,** <li> ^(Column zColumn is part of an index, PRIMARY KEY or UNIQUE ** constraint and the blob is being opened for read/write access)^,** <li> ^([foreign key constraints | Foreign key constraints] are enabled, ** column zColumn is part of a [child key] definition and the blob is** being opened for read/write access)^.** </ul>**** ^Unless it returns SQLITE_MISUSE, this function sets the ** [database connection] error code and message accessible via ** [sqlite3_errcode()] and [sqlite3_errmsg()] and related functions. ****** ^(If the row that a BLOB handle points to is modified by an** [UPDATE], [DELETE], or by [ON CONFLICT] side-effects** then the BLOB handle is marked as "expired".** This is true if any column of the row is changed, even a column** other than the one the BLOB handle is open on.)^** ^Calls to [sqlite3_blob_read()] and [sqlite3_blob_write()] for** an expired BLOB handle fail with a return code of [SQLITE_ABORT].** ^(Changes written into a BLOB prior to the BLOB expiring are not** rolled back by the expiration of the BLOB. Such changes will eventually** commit if the transaction continues to completion.)^**** ^Use the [sqlite3_blob_bytes()] interface to determine the size of** the opened blob. ^The size of a blob may not be changed by this** interface. Use the [UPDATE] SQL command to change the size of a** blob.**** ^The [sqlite3_bind_zeroblob()] and [sqlite3_result_zeroblob()] interfaces** and the built-in [zeroblob] SQL function may be used to create a ** zero-filled blob to read or write using the incremental-blob interface.**** To avoid a resource leak, every open [BLOB handle] should eventually** be released by a call to [sqlite3_blob_close()].*/SQLITE_APIintsqlite3_blob_open(sqlite3*,constchar*zDb,constchar*zTable,constchar*zColumn,sqlite3_int64iRow,intflags,sqlite3_blob**ppBlob);/*** CAPI3REF: Move a BLOB Handle to a New Row** METHOD: sqlite3_blob**** ^This function is used to move an existing blob handle so that it points** to a different row of the same database table. ^The new row is identified** by the rowid value passed as the second argument. Only the row can be** changed. ^The database, table and column on which the blob handle is open** remain the same. Moving an existing blob handle to a new row can be** faster than closing the existing handle and opening a new one.**** ^(The new row must meet the same criteria as for [sqlite3_blob_open()] -** it must exist and there must be either a blob or text value stored in** the nominated column.)^ ^If the new row is not present in the table, or if** it does not contain a blob or text value, or if another error occurs, an** SQLite error code is returned and the blob handle is considered aborted.** ^All subsequent calls to [sqlite3_blob_read()], [sqlite3_blob_write()] or** [sqlite3_blob_reopen()] on an aborted blob handle immediately return** SQLITE_ABORT. ^Calling [sqlite3_blob_bytes()] on an aborted blob handle** always returns zero.**** ^This function sets the database handle error code and message.*/SQLITE_APIintsqlite3_blob_reopen(sqlite3_blob*,sqlite3_int64);/*** CAPI3REF: Close A BLOB Handle** DESTRUCTOR: sqlite3_blob**** ^This function closes an open [BLOB handle]. ^(The BLOB handle is closed** unconditionally. Even if this routine returns an error code, the ** handle is still closed.)^**** ^If the blob handle being closed was opened for read-write access, and if** the database is in auto-commit mode and there are no other open read-write** blob handles or active write statements, the current transaction is** committed. ^If an error occurs while committing the transaction, an error** code is returned and the transaction rolled back.**** Calling this function with an argument that is not a NULL pointer or an** open blob handle results in undefined behaviour. ^Calling this routine ** with a null pointer (such as would be returned by a failed call to ** [sqlite3_blob_open()]) is a harmless no-op. ^Otherwise, if this function** is passed a valid open blob handle, the values returned by the ** sqlite3_errcode() and sqlite3_errmsg() functions are set before returning.*/SQLITE_APIintsqlite3_blob_close(sqlite3_blob*);/*** CAPI3REF: Return The Size Of An Open BLOB** METHOD: sqlite3_blob**** ^Returns the size in bytes of the BLOB accessible via the ** successfully opened [BLOB handle] in its only argument. ^The** incremental blob I/O routines can only read or overwriting existing** blob content; they cannot change the size of a blob.**** This routine only works on a [BLOB handle] which has been created** by a prior successful call to [sqlite3_blob_open()] and which has not** been closed by [sqlite3_blob_close()]. Passing any other pointer in** to this routine results in undefined and probably undesirable behavior.*/SQLITE_APIintsqlite3_blob_bytes(sqlite3_blob*);/*** CAPI3REF: Read Data From A BLOB Incrementally** METHOD: sqlite3_blob**** ^(This function is used to read data from an open [BLOB handle] into a** caller-supplied buffer. N bytes of data are copied into buffer Z** from the open BLOB, starting at offset iOffset.)^**** ^If offset iOffset is less than N bytes from the end of the BLOB,** [SQLITE_ERROR] is returned and no data is read. ^If N or iOffset is** less than zero, [SQLITE_ERROR] is returned and no data is read.** ^The size of the blob (and hence the maximum value of N+iOffset)** can be determined using the [sqlite3_blob_bytes()] interface.**** ^An attempt to read from an expired [BLOB handle] fails with an** error code of [SQLITE_ABORT].**** ^(On success, sqlite3_blob_read() returns SQLITE_OK.** Otherwise, an [error code] or an [extended error code] is returned.)^**** This routine only works on a [BLOB handle] which has been created** by a prior successful call to [sqlite3_blob_open()] and which has not** been closed by [sqlite3_blob_close()]. Passing any other pointer in** to this routine results in undefined and probably undesirable behavior.**** See also: [sqlite3_blob_write()].*/SQLITE_APIintsqlite3_blob_read(sqlite3_blob*,void*Z,intN,intiOffset);/*** CAPI3REF: Write Data Into A BLOB Incrementally** METHOD: sqlite3_blob**** ^(This function is used to write data into an open [BLOB handle] from a** caller-supplied buffer. N bytes of data are copied from the buffer Z** into the open BLOB, starting at offset iOffset.)^**** ^(On success, sqlite3_blob_write() returns SQLITE_OK.** Otherwise, an [error code] or an [extended error code] is returned.)^** ^Unless SQLITE_MISUSE is returned, this function sets the ** [database connection] error code and message accessible via ** [sqlite3_errcode()] and [sqlite3_errmsg()] and related functions. **** ^If the [BLOB handle] passed as the first argument was not opened for** writing (the flags parameter to [sqlite3_blob_open()] was zero),** this function returns [SQLITE_READONLY].**** This function may only modify the contents of the BLOB; it is** not possible to increase the size of a BLOB using this API.** ^If offset iOffset is less than N bytes from the end of the BLOB,** [SQLITE_ERROR] is returned and no data is written. The size of the ** BLOB (and hence the maximum value of N+iOffset) can be determined ** using the [sqlite3_blob_bytes()] interface. ^If N or iOffset are less ** than zero [SQLITE_ERROR] is returned and no data is written.**** ^An attempt to write to an expired [BLOB handle] fails with an** error code of [SQLITE_ABORT]. ^Writes to the BLOB that occurred** before the [BLOB handle] expired are not rolled back by the** expiration of the handle, though of course those changes might** have been overwritten by the statement that expired the BLOB handle** or by other independent statements.**** This routine only works on a [BLOB handle] which has been created** by a prior successful call to [sqlite3_blob_open()] and which has not** been closed by [sqlite3_blob_close()]. Passing any other pointer in** to this routine results in undefined and probably undesirable behavior.**** See also: [sqlite3_blob_read()].*/SQLITE_APIintsqlite3_blob_write(sqlite3_blob*,constvoid*z,intn,intiOffset);/*** CAPI3REF: Virtual File System Objects**** A virtual filesystem (VFS) is an [sqlite3_vfs] object** that SQLite uses to interact** with the underlying operating system. Most SQLite builds come with a** single default VFS that is appropriate for the host computer.** New VFSes can be registered and existing VFSes can be unregistered.** The following interfaces are provided.**** ^The sqlite3_vfs_find() interface returns a pointer to a VFS given its name.** ^Names are case sensitive.** ^Names are zero-terminated UTF-8 strings.** ^If there is no match, a NULL pointer is returned.** ^If zVfsName is NULL then the default VFS is returned.**** ^New VFSes are registered with sqlite3_vfs_register().** ^Each new VFS becomes the default VFS if the makeDflt flag is set.** ^The same VFS can be registered multiple times without injury.** ^To make an existing VFS into the default VFS, register it again** with the makeDflt flag set. If two different VFSes with the** same name are registered, the behavior is undefined. If a** VFS is registered with a name that is NULL or an empty string,** then the behavior is undefined.**** ^Unregister a VFS with the sqlite3_vfs_unregister() interface.** ^(If the default VFS is unregistered, another VFS is chosen as** the default. The choice for the new VFS is arbitrary.)^*/SQLITE_APIsqlite3_vfs*sqlite3_vfs_find(constchar*zVfsName);SQLITE_APIintsqlite3_vfs_register(sqlite3_vfs*,intmakeDflt);SQLITE_APIintsqlite3_vfs_unregister(sqlite3_vfs*);/*** CAPI3REF: Mutexes**** The SQLite core uses these routines for thread** synchronization. Though they are intended for internal** use by SQLite, code that links against SQLite is** permitted to use any of these routines.**** The SQLite source code contains multiple implementations** of these mutex routines. An appropriate implementation** is selected automatically at compile-time. The following** implementations are available in the SQLite core:**** <ul>** <li> SQLITE_MUTEX_PTHREADS** <li> SQLITE_MUTEX_W32** <li> SQLITE_MUTEX_NOOP** </ul>**** The SQLITE_MUTEX_NOOP implementation is a set of routines** that does no real locking and is appropriate for use in** a single-threaded application. The SQLITE_MUTEX_PTHREADS and** SQLITE_MUTEX_W32 implementations are appropriate for use on Unix** and Windows.**** If SQLite is compiled with the SQLITE_MUTEX_APPDEF preprocessor** macro defined (with "-DSQLITE_MUTEX_APPDEF=1"), then no mutex** implementation is included with the library. In this case the** application must supply a custom mutex implementation using the** [SQLITE_CONFIG_MUTEX] option of the sqlite3_config() function** before calling sqlite3_initialize() or any other public sqlite3_** function that calls sqlite3_initialize().**** ^The sqlite3_mutex_alloc() routine allocates a new** mutex and returns a pointer to it. ^The sqlite3_mutex_alloc()** routine returns NULL if it is unable to allocate the requested** mutex. The argument to sqlite3_mutex_alloc() must one of these** integer constants:**** <ul>** <li> SQLITE_MUTEX_FAST** <li> SQLITE_MUTEX_RECURSIVE** <li> SQLITE_MUTEX_STATIC_MASTER** <li> SQLITE_MUTEX_STATIC_MEM** <li> SQLITE_MUTEX_STATIC_OPEN** <li> SQLITE_MUTEX_STATIC_PRNG** <li> SQLITE_MUTEX_STATIC_LRU** <li> SQLITE_MUTEX_STATIC_PMEM** <li> SQLITE_MUTEX_STATIC_APP1** <li> SQLITE_MUTEX_STATIC_APP2** <li> SQLITE_MUTEX_STATIC_APP3** <li> SQLITE_MUTEX_STATIC_VFS1** <li> SQLITE_MUTEX_STATIC_VFS2** <li> SQLITE_MUTEX_STATIC_VFS3** </ul>**** ^The first two constants (SQLITE_MUTEX_FAST and SQLITE_MUTEX_RECURSIVE)** cause sqlite3_mutex_alloc() to create** a new mutex. ^The new mutex is recursive when SQLITE_MUTEX_RECURSIVE** is used but not necessarily so when SQLITE_MUTEX_FAST is used.** The mutex implementation does not need to make a distinction** between SQLITE_MUTEX_RECURSIVE and SQLITE_MUTEX_FAST if it does** not want to. SQLite will only request a recursive mutex in** cases where it really needs one. If a faster non-recursive mutex** implementation is available on the host platform, the mutex subsystem** might return such a mutex in response to SQLITE_MUTEX_FAST.**** ^The other allowed parameters to sqlite3_mutex_alloc() (anything other** than SQLITE_MUTEX_FAST and SQLITE_MUTEX_RECURSIVE) each return** a pointer to a static preexisting mutex. ^Nine static mutexes are** used by the current version of SQLite. Future versions of SQLite** may add additional static mutexes. Static mutexes are for internal** use by SQLite only. Applications that use SQLite mutexes should** use only the dynamic mutexes returned by SQLITE_MUTEX_FAST or** SQLITE_MUTEX_RECURSIVE.**** ^Note that if one of the dynamic mutex parameters (SQLITE_MUTEX_FAST** or SQLITE_MUTEX_RECURSIVE) is used then sqlite3_mutex_alloc()** returns a different mutex on every call. ^For the static** mutex types, the same mutex is returned on every call that has** the same type number.**** ^The sqlite3_mutex_free() routine deallocates a previously** allocated dynamic mutex. Attempting to deallocate a static** mutex results in undefined behavior.**** ^The sqlite3_mutex_enter() and sqlite3_mutex_try() routines attempt** to enter a mutex. ^If another thread is already within the mutex,** sqlite3_mutex_enter() will block and sqlite3_mutex_try() will return** SQLITE_BUSY. ^The sqlite3_mutex_try() interface returns [SQLITE_OK]** upon successful entry. ^(Mutexes created using** SQLITE_MUTEX_RECURSIVE can be entered multiple times by the same thread.** In such cases, the** mutex must be exited an equal number of times before another thread** can enter.)^ If the same thread tries to enter any mutex other** than an SQLITE_MUTEX_RECURSIVE more than once, the behavior is undefined.**** ^(Some systems (for example, Windows 95) do not support the operation** implemented by sqlite3_mutex_try(). On those systems, sqlite3_mutex_try()** will always return SQLITE_BUSY. The SQLite core only ever uses** sqlite3_mutex_try() as an optimization so this is acceptable ** behavior.)^**** ^The sqlite3_mutex_leave() routine exits a mutex that was** previously entered by the same thread. The behavior** is undefined if the mutex is not currently entered by the** calling thread or is not currently allocated.**** ^If the argument to sqlite3_mutex_enter(), sqlite3_mutex_try(), or** sqlite3_mutex_leave() is a NULL pointer, then all three routines** behave as no-ops.**** See also: [sqlite3_mutex_held()] and [sqlite3_mutex_notheld()].*/SQLITE_APIsqlite3_mutex*sqlite3_mutex_alloc(int);SQLITE_APIvoidsqlite3_mutex_free(sqlite3_mutex*);SQLITE_APIvoidsqlite3_mutex_enter(sqlite3_mutex*);SQLITE_APIintsqlite3_mutex_try(sqlite3_mutex*);SQLITE_APIvoidsqlite3_mutex_leave(sqlite3_mutex*);/*** CAPI3REF: Mutex Methods Object**** An instance of this structure defines the low-level routines** used to allocate and use mutexes.**** Usually, the default mutex implementations provided by SQLite are** sufficient, however the application has the option of substituting a custom** implementation for specialized deployments or systems for which SQLite** does not provide a suitable implementation. In this case, the application** creates and populates an instance of this structure to pass** to sqlite3_config() along with the [SQLITE_CONFIG_MUTEX] option.** Additionally, an instance of this structure can be used as an** output variable when querying the system for the current mutex** implementation, using the [SQLITE_CONFIG_GETMUTEX] option.**** ^The xMutexInit method defined by this structure is invoked as** part of system initialization by the sqlite3_initialize() function.** ^The xMutexInit routine is called by SQLite exactly once for each** effective call to [sqlite3_initialize()].**** ^The xMutexEnd method defined by this structure is invoked as** part of system shutdown by the sqlite3_shutdown() function. The** implementation of this method is expected to release all outstanding** resources obtained by the mutex methods implementation, especially** those obtained by the xMutexInit method. ^The xMutexEnd()** interface is invoked exactly once for each call to [sqlite3_shutdown()].**** ^(The remaining seven methods defined by this structure (xMutexAlloc,** xMutexFree, xMutexEnter, xMutexTry, xMutexLeave, xMutexHeld and** xMutexNotheld) implement the following interfaces (respectively):**** <ul>** <li> [sqlite3_mutex_alloc()] </li>** <li> [sqlite3_mutex_free()] </li>** <li> [sqlite3_mutex_enter()] </li>** <li> [sqlite3_mutex_try()] </li>** <li> [sqlite3_mutex_leave()] </li>** <li> [sqlite3_mutex_held()] </li>** <li> [sqlite3_mutex_notheld()] </li>** </ul>)^**** The only difference is that the public sqlite3_XXX functions enumerated** above silently ignore any invocations that pass a NULL pointer instead** of a valid mutex handle. The implementations of the methods defined** by this structure are not required to handle this case, the results** of passing a NULL pointer instead of a valid mutex handle are undefined** (i.e. it is acceptable to provide an implementation that segfaults if** it is passed a NULL pointer).**** The xMutexInit() method must be threadsafe. It must be harmless to** invoke xMutexInit() multiple times within the same process and without** intervening calls to xMutexEnd(). Second and subsequent calls to** xMutexInit() must be no-ops.**** xMutexInit() must not use SQLite memory allocation ([sqlite3_malloc()]** and its associates). Similarly, xMutexAlloc() must not use SQLite memory** allocation for a static mutex. ^However xMutexAlloc() may use SQLite** memory allocation for a fast or recursive mutex.**** ^SQLite will invoke the xMutexEnd() method when [sqlite3_shutdown()] is** called, but only if the prior call to xMutexInit returned SQLITE_OK.** If xMutexInit fails in any way, it is expected to clean up after itself** prior to returning.*/typedefstructsqlite3_mutex_methodssqlite3_mutex_methods;structsqlite3_mutex_methods{int(*xMutexInit)(void);int(*xMutexEnd)(void);sqlite3_mutex*(*xMutexAlloc)(int);void(*xMutexFree)(sqlite3_mutex*);void(*xMutexEnter)(sqlite3_mutex*);int(*xMutexTry)(sqlite3_mutex*);void(*xMutexLeave)(sqlite3_mutex*);int(*xMutexHeld)(sqlite3_mutex*);int(*xMutexNotheld)(sqlite3_mutex*);};/*** CAPI3REF: Mutex Verification Routines**** The sqlite3_mutex_held() and sqlite3_mutex_notheld() routines** are intended for use inside assert() statements. The SQLite core** never uses these routines except inside an assert() and applications** are advised to follow the lead of the core. The SQLite core only** provides implementations for these routines when it is compiled** with the SQLITE_DEBUG flag. External mutex implementations** are only required to provide these routines if SQLITE_DEBUG is** defined and if NDEBUG is not defined.**** These routines should return true if the mutex in their argument** is held or not held, respectively, by the calling thread.**** The implementation is not required to provide versions of these** routines that actually work. If the implementation does not provide working** versions of these routines, it should at least provide stubs that always** return true so that one does not get spurious assertion failures.**** If the argument to sqlite3_mutex_held() is a NULL pointer then** the routine should return 1. This seems counter-intuitive since** clearly the mutex cannot be held if it does not exist. But** the reason the mutex does not exist is because the build is not** using mutexes. And we do not want the assert() containing the** call to sqlite3_mutex_held() to fail, so a non-zero return is** the appropriate thing to do. The sqlite3_mutex_notheld()** interface should also return 1 when given a NULL pointer.*/#ifndef NDEBUGSQLITE_APIintsqlite3_mutex_held(sqlite3_mutex*);SQLITE_APIintsqlite3_mutex_notheld(sqlite3_mutex*);#endif/*** CAPI3REF: Mutex Types**** The [sqlite3_mutex_alloc()] interface takes a single argument** which is one of these integer constants.**** The set of static mutexes may change from one SQLite release to the** next. Applications that override the built-in mutex logic must be** prepared to accommodate additional static mutexes.*/#define SQLITE_MUTEX_FAST 0#define SQLITE_MUTEX_RECURSIVE 1#define SQLITE_MUTEX_STATIC_MASTER 2#define SQLITE_MUTEX_STATIC_MEM 3 /* sqlite3_malloc() */#define SQLITE_MUTEX_STATIC_MEM2 4 /* NOT USED */#define SQLITE_MUTEX_STATIC_OPEN 4 /* sqlite3BtreeOpen() */#define SQLITE_MUTEX_STATIC_PRNG 5 /* sqlite3_randomness() */#define SQLITE_MUTEX_STATIC_LRU 6 /* lru page list */#define SQLITE_MUTEX_STATIC_LRU2 7 /* NOT USED */#define SQLITE_MUTEX_STATIC_PMEM 7 /* sqlite3PageMalloc() */#define SQLITE_MUTEX_STATIC_APP1 8 /* For use by application */#define SQLITE_MUTEX_STATIC_APP2 9 /* For use by application */#define SQLITE_MUTEX_STATIC_APP3 10 /* For use by application */#define SQLITE_MUTEX_STATIC_VFS1 11 /* For use by built-in VFS */#define SQLITE_MUTEX_STATIC_VFS2 12 /* For use by extension VFS */#define SQLITE_MUTEX_STATIC_VFS3 13 /* For use by application VFS *//*** CAPI3REF: Retrieve the mutex for a database connection** METHOD: sqlite3**** ^This interface returns a pointer the [sqlite3_mutex] object that ** serializes access to the [database connection] given in the argument** when the [threading mode] is Serialized.** ^If the [threading mode] is Single-thread or Multi-thread then this** routine returns a NULL pointer.*/SQLITE_APIsqlite3_mutex*sqlite3_db_mutex(sqlite3*);/*** CAPI3REF: Low-Level Control Of Database Files** METHOD: sqlite3**** ^The [sqlite3_file_control()] interface makes a direct call to the** xFileControl method for the [sqlite3_io_methods] object associated** with a particular database identified by the second argument. ^The** name of the database is "main" for the main database or "temp" for the** TEMP database, or the name that appears after the AS keyword for** databases that are added using the [ATTACH] SQL command.** ^A NULL pointer can be used in place of "main" to refer to the** main database file.** ^The third and fourth parameters to this routine** are passed directly through to the second and third parameters of** the xFileControl method. ^The return value of the xFileControl** method becomes the return value of this routine.**** ^The SQLITE_FCNTL_FILE_POINTER value for the op parameter causes** a pointer to the underlying [sqlite3_file] object to be written into** the space pointed to by the 4th parameter. ^The SQLITE_FCNTL_FILE_POINTER** case is a short-circuit path which does not actually invoke the** underlying sqlite3_io_methods.xFileControl method.**** ^If the second parameter (zDbName) does not match the name of any** open database file, then SQLITE_ERROR is returned. ^This error** code is not remembered and will not be recalled by [sqlite3_errcode()]** or [sqlite3_errmsg()]. The underlying xFileControl method might** also return SQLITE_ERROR. There is no way to distinguish between** an incorrect zDbName and an SQLITE_ERROR return from the underlying** xFileControl method.**** See also: [SQLITE_FCNTL_LOCKSTATE]*/SQLITE_APIintsqlite3_file_control(sqlite3*,constchar*zDbName,intop,void*);/*** CAPI3REF: Testing Interface**** ^The sqlite3_test_control() interface is used to read out internal** state of SQLite and to inject faults into SQLite for testing** purposes. ^The first parameter is an operation code that determines** the number, meaning, and operation of all subsequent parameters.**** This interface is not for use by applications. It exists solely** for verifying the correct operation of the SQLite library. Depending** on how the SQLite library is compiled, this interface might not exist.**** The details of the operation codes, their meanings, the parameters** they take, and what they do are all subject to change without notice.** Unlike most of the SQLite API, this function is not guaranteed to** operate consistently from one release to the next.*/SQLITE_APIintsqlite3_test_control(intop,...);/*** CAPI3REF: Testing Interface Operation Codes**** These constants are the valid operation code parameters used** as the first argument to [sqlite3_test_control()].**** These parameters and their meanings are subject to change** without notice. These values are for testing purposes only.** Applications should not use any of these parameters or the** [sqlite3_test_control()] interface.*/#define SQLITE_TESTCTRL_FIRST 5#define SQLITE_TESTCTRL_PRNG_SAVE 5#define SQLITE_TESTCTRL_PRNG_RESTORE 6#define SQLITE_TESTCTRL_PRNG_RESET 7#define SQLITE_TESTCTRL_BITVEC_TEST 8#define SQLITE_TESTCTRL_FAULT_INSTALL 9#define SQLITE_TESTCTRL_BENIGN_MALLOC_HOOKS 10#define SQLITE_TESTCTRL_PENDING_BYTE 11#define SQLITE_TESTCTRL_ASSERT 12#define SQLITE_TESTCTRL_ALWAYS 13#define SQLITE_TESTCTRL_RESERVE 14#define SQLITE_TESTCTRL_OPTIMIZATIONS 15#define SQLITE_TESTCTRL_ISKEYWORD 16#define SQLITE_TESTCTRL_SCRATCHMALLOC 17#define SQLITE_TESTCTRL_LOCALTIME_FAULT 18#define SQLITE_TESTCTRL_EXPLAIN_STMT 19 /* NOT USED */#define SQLITE_TESTCTRL_ONCE_RESET_THRESHOLD 19#define SQLITE_TESTCTRL_NEVER_CORRUPT 20#define SQLITE_TESTCTRL_VDBE_COVERAGE 21#define SQLITE_TESTCTRL_BYTEORDER 22#define SQLITE_TESTCTRL_ISINIT 23#define SQLITE_TESTCTRL_SORTER_MMAP 24#define SQLITE_TESTCTRL_IMPOSTER 25#define SQLITE_TESTCTRL_LAST 25/*** CAPI3REF: SQLite Runtime Status**** ^These interfaces are used to retrieve runtime status information** about the performance of SQLite, and optionally to reset various** highwater marks. ^The first argument is an integer code for** the specific parameter to measure. ^(Recognized integer codes** are of the form [status parameters | SQLITE_STATUS_...].)^** ^The current value of the parameter is returned into *pCurrent.** ^The highest recorded value is returned in *pHighwater. ^If the** resetFlag is true, then the highest record value is reset after** *pHighwater is written. ^(Some parameters do not record the highest** value. For those parameters** nothing is written into *pHighwater and the resetFlag is ignored.)^** ^(Other parameters record only the highwater mark and not the current** value. For these latter parameters nothing is written into *pCurrent.)^**** ^The sqlite3_status() and sqlite3_status64() routines return** SQLITE_OK on success and a non-zero [error code] on failure.**** If either the current value or the highwater mark is too large to** be represented by a 32-bit integer, then the values returned by** sqlite3_status() are undefined.**** See also: [sqlite3_db_status()]*/SQLITE_APIintsqlite3_status(intop,int*pCurrent,int*pHighwater,intresetFlag);SQLITE_APIintsqlite3_status64(intop,sqlite3_int64*pCurrent,sqlite3_int64*pHighwater,intresetFlag);/*** CAPI3REF: Status Parameters** KEYWORDS: {status parameters}**** These integer constants designate various run-time status parameters** that can be returned by [sqlite3_status()].**** <dl>** [[SQLITE_STATUS_MEMORY_USED]] ^(<dt>SQLITE_STATUS_MEMORY_USED</dt>** <dd>This parameter is the current amount of memory checked out** using [sqlite3_malloc()], either directly or indirectly. The** figure includes calls made to [sqlite3_malloc()] by the application** and internal memory usage by the SQLite library. Scratch memory** controlled by [SQLITE_CONFIG_SCRATCH] and auxiliary page-cache** memory controlled by [SQLITE_CONFIG_PAGECACHE] is not included in** this parameter. The amount returned is the sum of the allocation** sizes as reported by the xSize method in [sqlite3_mem_methods].</dd>)^**** [[SQLITE_STATUS_MALLOC_SIZE]] ^(<dt>SQLITE_STATUS_MALLOC_SIZE</dt>** <dd>This parameter records the largest memory allocation request** handed to [sqlite3_malloc()] or [sqlite3_realloc()] (or their** internal equivalents). Only the value returned in the** *pHighwater parameter to [sqlite3_status()] is of interest. ** The value written into the *pCurrent parameter is undefined.</dd>)^**** [[SQLITE_STATUS_MALLOC_COUNT]] ^(<dt>SQLITE_STATUS_MALLOC_COUNT</dt>** <dd>This parameter records the number of separate memory allocations** currently checked out.</dd>)^**** [[SQLITE_STATUS_PAGECACHE_USED]] ^(<dt>SQLITE_STATUS_PAGECACHE_USED</dt>** <dd>This parameter returns the number of pages used out of the** [pagecache memory allocator] that was configured using ** [SQLITE_CONFIG_PAGECACHE]. The** value returned is in pages, not in bytes.</dd>)^**** [[SQLITE_STATUS_PAGECACHE_OVERFLOW]] ** ^(<dt>SQLITE_STATUS_PAGECACHE_OVERFLOW</dt>** <dd>This parameter returns the number of bytes of page cache** allocation which could not be satisfied by the [SQLITE_CONFIG_PAGECACHE]** buffer and where forced to overflow to [sqlite3_malloc()]. The** returned value includes allocations that overflowed because they** where too large (they were larger than the "sz" parameter to** [SQLITE_CONFIG_PAGECACHE]) and allocations that overflowed because** no space was left in the page cache.</dd>)^**** [[SQLITE_STATUS_PAGECACHE_SIZE]] ^(<dt>SQLITE_STATUS_PAGECACHE_SIZE</dt>** <dd>This parameter records the largest memory allocation request** handed to [pagecache memory allocator]. Only the value returned in the** *pHighwater parameter to [sqlite3_status()] is of interest. ** The value written into the *pCurrent parameter is undefined.</dd>)^**** [[SQLITE_STATUS_SCRATCH_USED]] ^(<dt>SQLITE_STATUS_SCRATCH_USED</dt>** <dd>This parameter returns the number of allocations used out of the** [scratch memory allocator] configured using** [SQLITE_CONFIG_SCRATCH]. The value returned is in allocations, not** in bytes. Since a single thread may only have one scratch allocation** outstanding at time, this parameter also reports the number of threads** using scratch memory at the same time.</dd>)^**** [[SQLITE_STATUS_SCRATCH_OVERFLOW]] ^(<dt>SQLITE_STATUS_SCRATCH_OVERFLOW</dt>** <dd>This parameter returns the number of bytes of scratch memory** allocation which could not be satisfied by the [SQLITE_CONFIG_SCRATCH]** buffer and where forced to overflow to [sqlite3_malloc()]. The values** returned include overflows because the requested allocation was too** larger (that is, because the requested allocation was larger than the** "sz" parameter to [SQLITE_CONFIG_SCRATCH]) and because no scratch buffer** slots were available.** </dd>)^**** [[SQLITE_STATUS_SCRATCH_SIZE]] ^(<dt>SQLITE_STATUS_SCRATCH_SIZE</dt>** <dd>This parameter records the largest memory allocation request** handed to [scratch memory allocator]. Only the value returned in the** *pHighwater parameter to [sqlite3_status()] is of interest. ** The value written into the *pCurrent parameter is undefined.</dd>)^**** [[SQLITE_STATUS_PARSER_STACK]] ^(<dt>SQLITE_STATUS_PARSER_STACK</dt>** <dd>The *pHighwater parameter records the deepest parser stack. ** The *pCurrent value is undefined. The *pHighwater value is only** meaningful if SQLite is compiled with [YYTRACKMAXSTACKDEPTH].</dd>)^** </dl>**** New status parameters may be added from time to time.*/#define SQLITE_STATUS_MEMORY_USED 0#define SQLITE_STATUS_PAGECACHE_USED 1#define SQLITE_STATUS_PAGECACHE_OVERFLOW 2#define SQLITE_STATUS_SCRATCH_USED 3#define SQLITE_STATUS_SCRATCH_OVERFLOW 4#define SQLITE_STATUS_MALLOC_SIZE 5#define SQLITE_STATUS_PARSER_STACK 6#define SQLITE_STATUS_PAGECACHE_SIZE 7#define SQLITE_STATUS_SCRATCH_SIZE 8#define SQLITE_STATUS_MALLOC_COUNT 9/*** CAPI3REF: Database Connection Status** METHOD: sqlite3**** ^This interface is used to retrieve runtime status information ** about a single [database connection]. ^The first argument is the** database connection object to be interrogated. ^The second argument** is an integer constant, taken from the set of** [SQLITE_DBSTATUS options], that** determines the parameter to interrogate. The set of ** [SQLITE_DBSTATUS options] is likely** to grow in future releases of SQLite.**** ^The current value of the requested parameter is written into *pCur** and the highest instantaneous value is written into *pHiwtr. ^If** the resetFlg is true, then the highest instantaneous value is** reset back down to the current value.**** ^The sqlite3_db_status() routine returns SQLITE_OK on success and a** non-zero [error code] on failure.**** See also: [sqlite3_status()] and [sqlite3_stmt_status()].*/SQLITE_APIintsqlite3_db_status(sqlite3*,intop,int*pCur,int*pHiwtr,intresetFlg);/*** CAPI3REF: Status Parameters for database connections** KEYWORDS: {SQLITE_DBSTATUS options}**** These constants are the available integer "verbs" that can be passed as** the second argument to the [sqlite3_db_status()] interface.**** New verbs may be added in future releases of SQLite. Existing verbs** might be discontinued. Applications should check the return code from** [sqlite3_db_status()] to make sure that the call worked.** The [sqlite3_db_status()] interface will return a non-zero error code** if a discontinued or unsupported verb is invoked.**** <dl>** [[SQLITE_DBSTATUS_LOOKASIDE_USED]] ^(<dt>SQLITE_DBSTATUS_LOOKASIDE_USED</dt>** <dd>This parameter returns the number of lookaside memory slots currently** checked out.</dd>)^**** [[SQLITE_DBSTATUS_LOOKASIDE_HIT]] ^(<dt>SQLITE_DBSTATUS_LOOKASIDE_HIT</dt>** <dd>This parameter returns the number malloc attempts that were ** satisfied using lookaside memory. Only the high-water value is meaningful;** the current value is always zero.)^**** [[SQLITE_DBSTATUS_LOOKASIDE_MISS_SIZE]]** ^(<dt>SQLITE_DBSTATUS_LOOKASIDE_MISS_SIZE</dt>** <dd>This parameter returns the number malloc attempts that might have** been satisfied using lookaside memory but failed due to the amount of** memory requested being larger than the lookaside slot size.** Only the high-water value is meaningful;** the current value is always zero.)^**** [[SQLITE_DBSTATUS_LOOKASIDE_MISS_FULL]]** ^(<dt>SQLITE_DBSTATUS_LOOKASIDE_MISS_FULL</dt>** <dd>This parameter returns the number malloc attempts that might have** been satisfied using lookaside memory but failed due to all lookaside** memory already being in use.** Only the high-water value is meaningful;** the current value is always zero.)^**** [[SQLITE_DBSTATUS_CACHE_USED]] ^(<dt>SQLITE_DBSTATUS_CACHE_USED</dt>** <dd>This parameter returns the approximate number of bytes of heap** memory used by all pager caches associated with the database connection.)^** ^The highwater mark associated with SQLITE_DBSTATUS_CACHE_USED is always 0.**** [[SQLITE_DBSTATUS_CACHE_USED_SHARED]] ** ^(<dt>SQLITE_DBSTATUS_CACHE_USED_SHARED</dt>** <dd>This parameter is similar to DBSTATUS_CACHE_USED, except that if a** pager cache is shared between two or more connections the bytes of heap** memory used by that pager cache is divided evenly between the attached** connections.)^ In other words, if none of the pager caches associated** with the database connection are shared, this request returns the same** value as DBSTATUS_CACHE_USED. Or, if one or more or the pager caches are** shared, the value returned by this call will be smaller than that returned** by DBSTATUS_CACHE_USED. ^The highwater mark associated with** SQLITE_DBSTATUS_CACHE_USED_SHARED is always 0.**** [[SQLITE_DBSTATUS_SCHEMA_USED]] ^(<dt>SQLITE_DBSTATUS_SCHEMA_USED</dt>** <dd>This parameter returns the approximate number of bytes of heap** memory used to store the schema for all databases associated** with the connection - main, temp, and any [ATTACH]-ed databases.)^ ** ^The full amount of memory used by the schemas is reported, even if the** schema memory is shared with other database connections due to** [shared cache mode] being enabled.** ^The highwater mark associated with SQLITE_DBSTATUS_SCHEMA_USED is always 0.**** [[SQLITE_DBSTATUS_STMT_USED]] ^(<dt>SQLITE_DBSTATUS_STMT_USED</dt>** <dd>This parameter returns the approximate number of bytes of heap** and lookaside memory used by all prepared statements associated with** the database connection.)^** ^The highwater mark associated with SQLITE_DBSTATUS_STMT_USED is always 0.** </dd>**** [[SQLITE_DBSTATUS_CACHE_HIT]] ^(<dt>SQLITE_DBSTATUS_CACHE_HIT</dt>** <dd>This parameter returns the number of pager cache hits that have** occurred.)^ ^The highwater mark associated with SQLITE_DBSTATUS_CACHE_HIT ** is always 0.** </dd>**** [[SQLITE_DBSTATUS_CACHE_MISS]] ^(<dt>SQLITE_DBSTATUS_CACHE_MISS</dt>** <dd>This parameter returns the number of pager cache misses that have** occurred.)^ ^The highwater mark associated with SQLITE_DBSTATUS_CACHE_MISS ** is always 0.** </dd>**** [[SQLITE_DBSTATUS_CACHE_WRITE]] ^(<dt>SQLITE_DBSTATUS_CACHE_WRITE</dt>** <dd>This parameter returns the number of dirty cache entries that have** been written to disk. Specifically, the number of pages written to the** wal file in wal mode databases, or the number of pages written to the** database file in rollback mode databases. Any pages written as part of** transaction rollback or database recovery operations are not included.** If an IO or other error occurs while writing a page to disk, the effect** on subsequent SQLITE_DBSTATUS_CACHE_WRITE requests is undefined.)^ ^The** highwater mark associated with SQLITE_DBSTATUS_CACHE_WRITE is always 0.** </dd>**** [[SQLITE_DBSTATUS_DEFERRED_FKS]] ^(<dt>SQLITE_DBSTATUS_DEFERRED_FKS</dt>** <dd>This parameter returns zero for the current value if and only if** all foreign key constraints (deferred or immediate) have been** resolved.)^ ^The highwater mark is always 0.** </dd>** </dl>*/#define SQLITE_DBSTATUS_LOOKASIDE_USED 0#define SQLITE_DBSTATUS_CACHE_USED 1#define SQLITE_DBSTATUS_SCHEMA_USED 2#define SQLITE_DBSTATUS_STMT_USED 3#define SQLITE_DBSTATUS_LOOKASIDE_HIT 4#define SQLITE_DBSTATUS_LOOKASIDE_MISS_SIZE 5#define SQLITE_DBSTATUS_LOOKASIDE_MISS_FULL 6#define SQLITE_DBSTATUS_CACHE_HIT 7#define SQLITE_DBSTATUS_CACHE_MISS 8#define SQLITE_DBSTATUS_CACHE_WRITE 9#define SQLITE_DBSTATUS_DEFERRED_FKS 10#define SQLITE_DBSTATUS_CACHE_USED_SHARED 11#define SQLITE_DBSTATUS_MAX 11 /* Largest defined DBSTATUS *//*** CAPI3REF: Prepared Statement Status** METHOD: sqlite3_stmt**** ^(Each prepared statement maintains various** [SQLITE_STMTSTATUS counters] that measure the number** of times it has performed specific operations.)^ These counters can** be used to monitor the performance characteristics of the prepared** statements. For example, if the number of table steps greatly exceeds** the number of table searches or result rows, that would tend to indicate** that the prepared statement is using a full table scan rather than** an index. **** ^(This interface is used to retrieve and reset counter values from** a [prepared statement]. The first argument is the prepared statement** object to be interrogated. The second argument** is an integer code for a specific [SQLITE_STMTSTATUS counter]** to be interrogated.)^** ^The current value of the requested counter is returned.** ^If the resetFlg is true, then the counter is reset to zero after this** interface call returns.**** See also: [sqlite3_status()] and [sqlite3_db_status()].*/SQLITE_APIintsqlite3_stmt_status(sqlite3_stmt*,intop,intresetFlg);/*** CAPI3REF: Status Parameters for prepared statements** KEYWORDS: {SQLITE_STMTSTATUS counter} {SQLITE_STMTSTATUS counters}**** These preprocessor macros define integer codes that name counter** values associated with the [sqlite3_stmt_status()] interface.** The meanings of the various counters are as follows:**** <dl>** [[SQLITE_STMTSTATUS_FULLSCAN_STEP]] <dt>SQLITE_STMTSTATUS_FULLSCAN_STEP</dt>** <dd>^This is the number of times that SQLite has stepped forward in** a table as part of a full table scan. Large numbers for this counter** may indicate opportunities for performance improvement through ** careful use of indices.</dd>**** [[SQLITE_STMTSTATUS_SORT]] <dt>SQLITE_STMTSTATUS_SORT</dt>** <dd>^This is the number of sort operations that have occurred.** A non-zero value in this counter may indicate an opportunity to** improvement performance through careful use of indices.</dd>**** [[SQLITE_STMTSTATUS_AUTOINDEX]] <dt>SQLITE_STMTSTATUS_AUTOINDEX</dt>** <dd>^This is the number of rows inserted into transient indices that** were created automatically in order to help joins run faster.** A non-zero value in this counter may indicate an opportunity to** improvement performance by adding permanent indices that do not** need to be reinitialized each time the statement is run.</dd>**** [[SQLITE_STMTSTATUS_VM_STEP]] <dt>SQLITE_STMTSTATUS_VM_STEP</dt>** <dd>^This is the number of virtual machine operations executed** by the prepared statement if that number is less than or equal** to 2147483647. The number of virtual machine operations can be ** used as a proxy for the total work done by the prepared statement.** If the number of virtual machine operations exceeds 2147483647** then the value returned by this statement status code is undefined.** </dd>** </dl>*/#define SQLITE_STMTSTATUS_FULLSCAN_STEP 1#define SQLITE_STMTSTATUS_SORT 2#define SQLITE_STMTSTATUS_AUTOINDEX 3#define SQLITE_STMTSTATUS_VM_STEP 4/*** CAPI3REF: Custom Page Cache Object**** The sqlite3_pcache type is opaque. It is implemented by** the pluggable module. The SQLite core has no knowledge of** its size or internal structure and never deals with the** sqlite3_pcache object except by holding and passing pointers** to the object.**** See [sqlite3_pcache_methods2] for additional information.*/typedefstructsqlite3_pcachesqlite3_pcache;/*** CAPI3REF: Custom Page Cache Object**** The sqlite3_pcache_page object represents a single page in the** page cache. The page cache will allocate instances of this** object. Various methods of the page cache use pointers to instances** of this object as parameters or as their return value.**** See [sqlite3_pcache_methods2] for additional information.*/typedefstructsqlite3_pcache_pagesqlite3_pcache_page;structsqlite3_pcache_page{void*pBuf;/* The content of the page */void*pExtra;/* Extra information associated with the page */};/*** CAPI3REF: Application Defined Page Cache.** KEYWORDS: {page cache}**** ^(The [sqlite3_config]([SQLITE_CONFIG_PCACHE2], ...) interface can** register an alternative page cache implementation by passing in an ** instance of the sqlite3_pcache_methods2 structure.)^** In many applications, most of the heap memory allocated by ** SQLite is used for the page cache.** By implementing a ** custom page cache using this API, an application can better control** the amount of memory consumed by SQLite, the way in which ** that memory is allocated and released, and the policies used to ** determine exactly which parts of a database file are cached and for ** how long.**** The alternative page cache mechanism is an** extreme measure that is only needed by the most demanding applications.** The built-in page cache is recommended for most uses.**** ^(The contents of the sqlite3_pcache_methods2 structure are copied to an** internal buffer by SQLite within the call to [sqlite3_config]. Hence** the application may discard the parameter after the call to** [sqlite3_config()] returns.)^**** [[the xInit() page cache method]]** ^(The xInit() method is called once for each effective ** call to [sqlite3_initialize()])^** (usually only once during the lifetime of the process). ^(The xInit()** method is passed a copy of the sqlite3_pcache_methods2.pArg value.)^** The intent of the xInit() method is to set up global data structures ** required by the custom page cache implementation. ** ^(If the xInit() method is NULL, then the ** built-in default page cache is used instead of the application defined** page cache.)^**** [[the xShutdown() page cache method]]** ^The xShutdown() method is called by [sqlite3_shutdown()].** It can be used to clean up ** any outstanding resources before process shutdown, if required.** ^The xShutdown() method may be NULL.**** ^SQLite automatically serializes calls to the xInit method,** so the xInit method need not be threadsafe. ^The** xShutdown method is only called from [sqlite3_shutdown()] so it does** not need to be threadsafe either. All other methods must be threadsafe** in multithreaded applications.**** ^SQLite will never invoke xInit() more than once without an intervening** call to xShutdown().**** [[the xCreate() page cache methods]]** ^SQLite invokes the xCreate() method to construct a new cache instance.** SQLite will typically create one cache instance for each open database file,** though this is not guaranteed. ^The** first parameter, szPage, is the size in bytes of the pages that must** be allocated by the cache. ^szPage will always a power of two. ^The** second parameter szExtra is a number of bytes of extra storage ** associated with each page cache entry. ^The szExtra parameter will** a number less than 250. SQLite will use the** extra szExtra bytes on each page to store metadata about the underlying** database page on disk. The value passed into szExtra depends** on the SQLite version, the target platform, and how SQLite was compiled.** ^The third argument to xCreate(), bPurgeable, is true if the cache being** created will be used to cache database pages of a file stored on disk, or** false if it is used for an in-memory database. The cache implementation** does not have to do anything special based with the value of bPurgeable;** it is purely advisory. ^On a cache where bPurgeable is false, SQLite will** never invoke xUnpin() except to deliberately delete a page.** ^In other words, calls to xUnpin() on a cache with bPurgeable set to** false will always have the "discard" flag set to true. ** ^Hence, a cache created with bPurgeable false will** never contain any unpinned pages.**** [[the xCachesize() page cache method]]** ^(The xCachesize() method may be called at any time by SQLite to set the** suggested maximum cache-size (number of pages stored by) the cache** instance passed as the first argument. This is the value configured using** the SQLite "[PRAGMA cache_size]" command.)^ As with the bPurgeable** parameter, the implementation is not required to do anything with this** value; it is advisory only.**** [[the xPagecount() page cache methods]]** The xPagecount() method must return the number of pages currently** stored in the cache, both pinned and unpinned.** ** [[the xFetch() page cache methods]]** The xFetch() method locates a page in the cache and returns a pointer to ** an sqlite3_pcache_page object associated with that page, or a NULL pointer.** The pBuf element of the returned sqlite3_pcache_page object will be a** pointer to a buffer of szPage bytes used to store the content of a ** single database page. The pExtra element of sqlite3_pcache_page will be** a pointer to the szExtra bytes of extra storage that SQLite has requested** for each entry in the page cache.**** The page to be fetched is determined by the key. ^The minimum key value** is 1. After it has been retrieved using xFetch, the page is considered** to be "pinned".**** If the requested page is already in the page cache, then the page cache** implementation must return a pointer to the page buffer with its content** intact. If the requested page is not already in the cache, then the** cache implementation should use the value of the createFlag** parameter to help it determined what action to take:**** <table border=1 width=85% align=center>** <tr><th> createFlag <th> Behavior when page is not already in cache** <tr><td> 0 <td> Do not allocate a new page. Return NULL.** <tr><td> 1 <td> Allocate a new page if it easy and convenient to do so.** Otherwise return NULL.** <tr><td> 2 <td> Make every effort to allocate a new page. Only return** NULL if allocating a new page is effectively impossible.** </table>**** ^(SQLite will normally invoke xFetch() with a createFlag of 0 or 1. SQLite** will only use a createFlag of 2 after a prior call with a createFlag of 1** failed.)^ In between the to xFetch() calls, SQLite may** attempt to unpin one or more cache pages by spilling the content of** pinned pages to disk and synching the operating system disk cache.**** [[the xUnpin() page cache method]]** ^xUnpin() is called by SQLite with a pointer to a currently pinned page** as its second argument. If the third parameter, discard, is non-zero,** then the page must be evicted from the cache.** ^If the discard parameter is** zero, then the page may be discarded or retained at the discretion of** page cache implementation. ^The page cache implementation** may choose to evict unpinned pages at any time.**** The cache must not perform any reference counting. A single ** call to xUnpin() unpins the page regardless of the number of prior calls ** to xFetch().**** [[the xRekey() page cache methods]]** The xRekey() method is used to change the key value associated with the** page passed as the second argument. If the cache** previously contains an entry associated with newKey, it must be** discarded. ^Any prior cache entry associated with newKey is guaranteed not** to be pinned.**** When SQLite calls the xTruncate() method, the cache must discard all** existing cache entries with page numbers (keys) greater than or equal** to the value of the iLimit parameter passed to xTruncate(). If any** of these pages are pinned, they are implicitly unpinned, meaning that** they can be safely discarded.**** [[the xDestroy() page cache method]]** ^The xDestroy() method is used to delete a cache allocated by xCreate().** All resources associated with the specified cache should be freed. ^After** calling the xDestroy() method, SQLite considers the [sqlite3_pcache*]** handle invalid, and will not use it with any other sqlite3_pcache_methods2** functions.**** [[the xShrink() page cache method]]** ^SQLite invokes the xShrink() method when it wants the page cache to** free up as much of heap memory as possible. The page cache implementation** is not obligated to free any memory, but well-behaved implementations should** do their best.*/typedefstructsqlite3_pcache_methods2sqlite3_pcache_methods2;structsqlite3_pcache_methods2{intiVersion;void*pArg;int(*xInit)(void*);void(*xShutdown)(void*);sqlite3_pcache*(*xCreate)(intszPage,intszExtra,intbPurgeable);void(*xCachesize)(sqlite3_pcache*,intnCachesize);int(*xPagecount)(sqlite3_pcache*);sqlite3_pcache_page*(*xFetch)(sqlite3_pcache*,unsignedkey,intcreateFlag);void(*xUnpin)(sqlite3_pcache*,sqlite3_pcache_page*,intdiscard);void(*xRekey)(sqlite3_pcache*,sqlite3_pcache_page*,unsignedoldKey,unsignednewKey);void(*xTruncate)(sqlite3_pcache*,unsignediLimit);void(*xDestroy)(sqlite3_pcache*);void(*xShrink)(sqlite3_pcache*);};/*** This is the obsolete pcache_methods object that has now been replaced** by sqlite3_pcache_methods2. This object is not used by SQLite. It is** retained in the header file for backwards compatibility only.*/typedefstructsqlite3_pcache_methodssqlite3_pcache_methods;structsqlite3_pcache_methods{void*pArg;int(*xInit)(void*);void(*xShutdown)(void*);sqlite3_pcache*(*xCreate)(intszPage,intbPurgeable);void(*xCachesize)(sqlite3_pcache*,intnCachesize);int(*xPagecount)(sqlite3_pcache*);void*(*xFetch)(sqlite3_pcache*,unsignedkey,intcreateFlag);void(*xUnpin)(sqlite3_pcache*,void*,intdiscard);void(*xRekey)(sqlite3_pcache*,void*,unsignedoldKey,unsignednewKey);void(*xTruncate)(sqlite3_pcache*,unsignediLimit);void(*xDestroy)(sqlite3_pcache*);};/*** CAPI3REF: Online Backup Object**** The sqlite3_backup object records state information about an ongoing** online backup operation. ^The sqlite3_backup object is created by** a call to [sqlite3_backup_init()] and is destroyed by a call to** [sqlite3_backup_finish()].**** See Also: [Using the SQLite Online Backup API]*/typedefstructsqlite3_backupsqlite3_backup;/*** CAPI3REF: Online Backup API.**** The backup API copies the content of one database into another.** It is useful either for creating backups of databases or** for copying in-memory databases to or from persistent files. **** See Also: [Using the SQLite Online Backup API]**** ^SQLite holds a write transaction open on the destination database file** for the duration of the backup operation.** ^The source database is read-locked only while it is being read;** it is not locked continuously for the entire backup operation.** ^Thus, the backup may be performed on a live source database without** preventing other database connections from** reading or writing to the source database while the backup is underway.** ** ^(To perform a backup operation: ** <ol>** <li><b>sqlite3_backup_init()</b> is called once to initialize the** backup, ** <li><b>sqlite3_backup_step()</b> is called one or more times to transfer ** the data between the two databases, and finally** <li><b>sqlite3_backup_finish()</b> is called to release all resources ** associated with the backup operation. ** </ol>)^** There should be exactly one call to sqlite3_backup_finish() for each** successful call to sqlite3_backup_init().**** [[sqlite3_backup_init()]] <b>sqlite3_backup_init()</b>**** ^The D and N arguments to sqlite3_backup_init(D,N,S,M) are the ** [database connection] associated with the destination database ** and the database name, respectively.** ^The database name is "main" for the main database, "temp" for the** temporary database, or the name specified after the AS keyword in** an [ATTACH] statement for an attached database.** ^The S and M arguments passed to ** sqlite3_backup_init(D,N,S,M) identify the [database connection]** and database name of the source database, respectively.** ^The source and destination [database connections] (parameters S and D)** must be different or else sqlite3_backup_init(D,N,S,M) will fail with** an error.**** ^A call to sqlite3_backup_init() will fail, returning NULL, if ** there is already a read or read-write transaction open on the ** destination database.**** ^If an error occurs within sqlite3_backup_init(D,N,S,M), then NULL is** returned and an error code and error message are stored in the** destination [database connection] D.** ^The error code and message for the failed call to sqlite3_backup_init()** can be retrieved using the [sqlite3_errcode()], [sqlite3_errmsg()], and/or** [sqlite3_errmsg16()] functions.** ^A successful call to sqlite3_backup_init() returns a pointer to an** [sqlite3_backup] object.** ^The [sqlite3_backup] object may be used with the sqlite3_backup_step() and** sqlite3_backup_finish() functions to perform the specified backup ** operation.**** [[sqlite3_backup_step()]] <b>sqlite3_backup_step()</b>**** ^Function sqlite3_backup_step(B,N) will copy up to N pages between ** the source and destination databases specified by [sqlite3_backup] object B.** ^If N is negative, all remaining source pages are copied. ** ^If sqlite3_backup_step(B,N) successfully copies N pages and there** are still more pages to be copied, then the function returns [SQLITE_OK].** ^If sqlite3_backup_step(B,N) successfully finishes copying all pages** from source to destination, then it returns [SQLITE_DONE].** ^If an error occurs while running sqlite3_backup_step(B,N),** then an [error code] is returned. ^As well as [SQLITE_OK] and** [SQLITE_DONE], a call to sqlite3_backup_step() may return [SQLITE_READONLY],** [SQLITE_NOMEM], [SQLITE_BUSY], [SQLITE_LOCKED], or an** [SQLITE_IOERR_ACCESS | SQLITE_IOERR_XXX] extended error code.**** ^(The sqlite3_backup_step() might return [SQLITE_READONLY] if** <ol>** <li> the destination database was opened read-only, or** <li> the destination database is using write-ahead-log journaling** and the destination and source page sizes differ, or** <li> the destination database is an in-memory database and the** destination and source page sizes differ.** </ol>)^**** ^If sqlite3_backup_step() cannot obtain a required file-system lock, then** the [sqlite3_busy_handler | busy-handler function]** is invoked (if one is specified). ^If the ** busy-handler returns non-zero before the lock is available, then ** [SQLITE_BUSY] is returned to the caller. ^In this case the call to** sqlite3_backup_step() can be retried later. ^If the source** [database connection]** is being used to write to the source database when sqlite3_backup_step()** is called, then [SQLITE_LOCKED] is returned immediately. ^Again, in this** case the call to sqlite3_backup_step() can be retried later on. ^(If** [SQLITE_IOERR_ACCESS | SQLITE_IOERR_XXX], [SQLITE_NOMEM], or** [SQLITE_READONLY] is returned, then ** there is no point in retrying the call to sqlite3_backup_step(). These ** errors are considered fatal.)^ The application must accept ** that the backup operation has failed and pass the backup operation handle ** to the sqlite3_backup_finish() to release associated resources.**** ^The first call to sqlite3_backup_step() obtains an exclusive lock** on the destination file. ^The exclusive lock is not released until either ** sqlite3_backup_finish() is called or the backup operation is complete ** and sqlite3_backup_step() returns [SQLITE_DONE]. ^Every call to** sqlite3_backup_step() obtains a [shared lock] on the source database that** lasts for the duration of the sqlite3_backup_step() call.** ^Because the source database is not locked between calls to** sqlite3_backup_step(), the source database may be modified mid-way** through the backup process. ^If the source database is modified by an** external process or via a database connection other than the one being** used by the backup operation, then the backup will be automatically** restarted by the next call to sqlite3_backup_step(). ^If the source ** database is modified by the using the same database connection as is used** by the backup operation, then the backup database is automatically** updated at the same time.**** [[sqlite3_backup_finish()]] <b>sqlite3_backup_finish()</b>**** When sqlite3_backup_step() has returned [SQLITE_DONE], or when the ** application wishes to abandon the backup operation, the application** should destroy the [sqlite3_backup] by passing it to sqlite3_backup_finish().** ^The sqlite3_backup_finish() interfaces releases all** resources associated with the [sqlite3_backup] object. ** ^If sqlite3_backup_step() has not yet returned [SQLITE_DONE], then any** active write-transaction on the destination database is rolled back.** The [sqlite3_backup] object is invalid** and may not be used following a call to sqlite3_backup_finish().**** ^The value returned by sqlite3_backup_finish is [SQLITE_OK] if no** sqlite3_backup_step() errors occurred, regardless or whether or not** sqlite3_backup_step() completed.** ^If an out-of-memory condition or IO error occurred during any prior** sqlite3_backup_step() call on the same [sqlite3_backup] object, then** sqlite3_backup_finish() returns the corresponding [error code].**** ^A return of [SQLITE_BUSY] or [SQLITE_LOCKED] from sqlite3_backup_step()** is not a permanent error and does not affect the return value of** sqlite3_backup_finish().**** [[sqlite3_backup_remaining()]] [[sqlite3_backup_pagecount()]]** <b>sqlite3_backup_remaining() and sqlite3_backup_pagecount()</b>**** ^The sqlite3_backup_remaining() routine returns the number of pages still** to be backed up at the conclusion of the most recent sqlite3_backup_step().** ^The sqlite3_backup_pagecount() routine returns the total number of pages** in the source database at the conclusion of the most recent** sqlite3_backup_step().** ^(The values returned by these functions are only updated by** sqlite3_backup_step(). If the source database is modified in a way that** changes the size of the source database or the number of pages remaining,** those changes are not reflected in the output of sqlite3_backup_pagecount()** and sqlite3_backup_remaining() until after the next** sqlite3_backup_step().)^**** <b>Concurrent Usage of Database Handles</b>**** ^The source [database connection] may be used by the application for other** purposes while a backup operation is underway or being initialized.** ^If SQLite is compiled and configured to support threadsafe database** connections, then the source database connection may be used concurrently** from within other threads.**** However, the application must guarantee that the destination ** [database connection] is not passed to any other API (by any thread) after ** sqlite3_backup_init() is called and before the corresponding call to** sqlite3_backup_finish(). SQLite does not currently check to see** if the application incorrectly accesses the destination [database connection]** and so no error code is reported, but the operations may malfunction** nevertheless. Use of the destination database connection while a** backup is in progress might also also cause a mutex deadlock.**** If running in [shared cache mode], the application must** guarantee that the shared cache used by the destination database** is not accessed while the backup is running. In practice this means** that the application must guarantee that the disk file being ** backed up to is not accessed by any connection within the process,** not just the specific connection that was passed to sqlite3_backup_init().**** The [sqlite3_backup] object itself is partially threadsafe. Multiple ** threads may safely make multiple concurrent calls to sqlite3_backup_step().** However, the sqlite3_backup_remaining() and sqlite3_backup_pagecount()** APIs are not strictly speaking threadsafe. If they are invoked at the** same time as another thread is invoking sqlite3_backup_step() it is** possible that they return invalid values.*/SQLITE_APIsqlite3_backup*sqlite3_backup_init(sqlite3*pDest,/* Destination database handle */constchar*zDestName,/* Destination database name */sqlite3*pSource,/* Source database handle */constchar*zSourceName/* Source database name */);SQLITE_APIintsqlite3_backup_step(sqlite3_backup*p,intnPage);SQLITE_APIintsqlite3_backup_finish(sqlite3_backup*p);SQLITE_APIintsqlite3_backup_remaining(sqlite3_backup*p);SQLITE_APIintsqlite3_backup_pagecount(sqlite3_backup*p);/*** CAPI3REF: Unlock Notification** METHOD: sqlite3**** ^When running in shared-cache mode, a database operation may fail with** an [SQLITE_LOCKED] error if the required locks on the shared-cache or** individual tables within the shared-cache cannot be obtained. See** [SQLite Shared-Cache Mode] for a description of shared-cache locking. ** ^This API may be used to register a callback that SQLite will invoke ** when the connection currently holding the required lock relinquishes it.** ^This API is only available if the library was compiled with the** [SQLITE_ENABLE_UNLOCK_NOTIFY] C-preprocessor symbol defined.**** See Also: [Using the SQLite Unlock Notification Feature].**** ^Shared-cache locks are released when a database connection concludes** its current transaction, either by committing it or rolling it back. **** ^When a connection (known as the blocked connection) fails to obtain a** shared-cache lock and SQLITE_LOCKED is returned to the caller, the** identity of the database connection (the blocking connection) that** has locked the required resource is stored internally. ^After an ** application receives an SQLITE_LOCKED error, it may call the** sqlite3_unlock_notify() method with the blocked connection handle as ** the first argument to register for a callback that will be invoked** when the blocking connections current transaction is concluded. ^The** callback is invoked from within the [sqlite3_step] or [sqlite3_close]** call that concludes the blocking connections transaction.**** ^(If sqlite3_unlock_notify() is called in a multi-threaded application,** there is a chance that the blocking connection will have already** concluded its transaction by the time sqlite3_unlock_notify() is invoked.** If this happens, then the specified callback is invoked immediately,** from within the call to sqlite3_unlock_notify().)^**** ^If the blocked connection is attempting to obtain a write-lock on a** shared-cache table, and more than one other connection currently holds** a read-lock on the same table, then SQLite arbitrarily selects one of ** the other connections to use as the blocking connection.**** ^(There may be at most one unlock-notify callback registered by a ** blocked connection. If sqlite3_unlock_notify() is called when the** blocked connection already has a registered unlock-notify callback,** then the new callback replaces the old.)^ ^If sqlite3_unlock_notify() is** called with a NULL pointer as its second argument, then any existing** unlock-notify callback is canceled. ^The blocked connections ** unlock-notify callback may also be canceled by closing the blocked** connection using [sqlite3_close()].**** The unlock-notify callback is not reentrant. If an application invokes** any sqlite3_xxx API functions from within an unlock-notify callback, a** crash or deadlock may be the result.**** ^Unless deadlock is detected (see below), sqlite3_unlock_notify() always** returns SQLITE_OK.**** <b>Callback Invocation Details</b>**** When an unlock-notify callback is registered, the application provides a ** single void* pointer that is passed to the callback when it is invoked.** However, the signature of the callback function allows SQLite to pass** it an array of void* context pointers. The first argument passed to** an unlock-notify callback is a pointer to an array of void* pointers,** and the second is the number of entries in the array.**** When a blocking connections transaction is concluded, there may be** more than one blocked connection that has registered for an unlock-notify** callback. ^If two or more such blocked connections have specified the** same callback function, then instead of invoking the callback function** multiple times, it is invoked once with the set of void* context pointers** specified by the blocked connections bundled together into an array.** This gives the application an opportunity to prioritize any actions ** related to the set of unblocked database connections.**** <b>Deadlock Detection</b>**** Assuming that after registering for an unlock-notify callback a ** database waits for the callback to be issued before taking any further** action (a reasonable assumption), then using this API may cause the** application to deadlock. For example, if connection X is waiting for** connection Y's transaction to be concluded, and similarly connection** Y is waiting on connection X's transaction, then neither connection** will proceed and the system may remain deadlocked indefinitely.**** To avoid this scenario, the sqlite3_unlock_notify() performs deadlock** detection. ^If a given call to sqlite3_unlock_notify() would put the** system in a deadlocked state, then SQLITE_LOCKED is returned and no** unlock-notify callback is registered. The system is said to be in** a deadlocked state if connection A has registered for an unlock-notify** callback on the conclusion of connection B's transaction, and connection** B has itself registered for an unlock-notify callback when connection** A's transaction is concluded. ^Indirect deadlock is also detected, so** the system is also considered to be deadlocked if connection B has** registered for an unlock-notify callback on the conclusion of connection** C's transaction, where connection C is waiting on connection A. ^Any** number of levels of indirection are allowed.**** <b>The "DROP TABLE" Exception</b>**** When a call to [sqlite3_step()] returns SQLITE_LOCKED, it is almost ** always appropriate to call sqlite3_unlock_notify(). There is however,** one exception. When executing a "DROP TABLE" or "DROP INDEX" statement,** SQLite checks if there are any currently executing SELECT statements** that belong to the same connection. If there are, SQLITE_LOCKED is** returned. In this case there is no "blocking connection", so invoking** sqlite3_unlock_notify() results in the unlock-notify callback being** invoked immediately. If the application then re-attempts the "DROP TABLE"** or "DROP INDEX" query, an infinite loop might be the result.**** One way around this problem is to check the extended error code returned** by an sqlite3_step() call. ^(If there is a blocking connection, then the** extended error code is set to SQLITE_LOCKED_SHAREDCACHE. Otherwise, in** the special "DROP TABLE/INDEX" case, the extended error code is just ** SQLITE_LOCKED.)^*/SQLITE_APIintsqlite3_unlock_notify(sqlite3*pBlocked,/* Waiting connection */void(*xNotify)(void**apArg,intnArg),/* Callback function to invoke */void*pNotifyArg/* Argument to pass to xNotify */);/*** CAPI3REF: String Comparison**** ^The [sqlite3_stricmp()] and [sqlite3_strnicmp()] APIs allow applications** and extensions to compare the contents of two buffers containing UTF-8** strings in a case-independent fashion, using the same definition of "case** independence" that SQLite uses internally when comparing identifiers.*/SQLITE_APIintsqlite3_stricmp(constchar*,constchar*);SQLITE_APIintsqlite3_strnicmp(constchar*,constchar*,int);/*** CAPI3REF: String Globbing*** ^The [sqlite3_strglob(P,X)] interface returns zero if and only if** string X matches the [GLOB] pattern P.** ^The definition of [GLOB] pattern matching used in** [sqlite3_strglob(P,X)] is the same as for the "X GLOB P" operator in the** SQL dialect understood by SQLite. ^The [sqlite3_strglob(P,X)] function** is case sensitive.**** Note that this routine returns zero on a match and non-zero if the strings** do not match, the same as [sqlite3_stricmp()] and [sqlite3_strnicmp()].**** See also: [sqlite3_strlike()].*/SQLITE_APIintsqlite3_strglob(constchar*zGlob,constchar*zStr);/*** CAPI3REF: String LIKE Matching*** ^The [sqlite3_strlike(P,X,E)] interface returns zero if and only if** string X matches the [LIKE] pattern P with escape character E.** ^The definition of [LIKE] pattern matching used in** [sqlite3_strlike(P,X,E)] is the same as for the "X LIKE P ESCAPE E"** operator in the SQL dialect understood by SQLite. ^For "X LIKE P" without** the ESCAPE clause, set the E parameter of [sqlite3_strlike(P,X,E)] to 0.** ^As with the LIKE operator, the [sqlite3_strlike(P,X,E)] function is case** insensitive - equivalent upper and lower case ASCII characters match** one another.**** ^The [sqlite3_strlike(P,X,E)] function matches Unicode characters, though** only ASCII characters are case folded.**** Note that this routine returns zero on a match and non-zero if the strings** do not match, the same as [sqlite3_stricmp()] and [sqlite3_strnicmp()].**** See also: [sqlite3_strglob()].*/SQLITE_APIintsqlite3_strlike(constchar*zGlob,constchar*zStr,unsignedintcEsc);/*** CAPI3REF: Error Logging Interface**** ^The [sqlite3_log()] interface writes a message into the [error log]** established by the [SQLITE_CONFIG_LOG] option to [sqlite3_config()].** ^If logging is enabled, the zFormat string and subsequent arguments are** used with [sqlite3_snprintf()] to generate the final output string.**** The sqlite3_log() interface is intended for use by extensions such as** virtual tables, collating functions, and SQL functions. While there is** nothing to prevent an application from calling sqlite3_log(), doing so** is considered bad form.**** The zFormat string must not be NULL.**** To avoid deadlocks and other threading problems, the sqlite3_log() routine** will not use dynamically allocated memory. The log message is stored in** a fixed-length buffer on the stack. If the log message is longer than** a few hundred characters, it will be truncated to the length of the** buffer.*/SQLITE_APIvoidsqlite3_log(intiErrCode,constchar*zFormat,...);/*** CAPI3REF: Write-Ahead Log Commit Hook** METHOD: sqlite3**** ^The [sqlite3_wal_hook()] function is used to register a callback that** is invoked each time data is committed to a database in wal mode.**** ^(The callback is invoked by SQLite after the commit has taken place and ** the associated write-lock on the database released)^, so the implementation ** may read, write or [checkpoint] the database as required.**** ^The first parameter passed to the callback function when it is invoked** is a copy of the third parameter passed to sqlite3_wal_hook() when** registering the callback. ^The second is a copy of the database handle.** ^The third parameter is the name of the database that was written to -** either "main" or the name of an [ATTACH]-ed database. ^The fourth parameter** is the number of pages currently in the write-ahead log file,** including those that were just committed.**** The callback function should normally return [SQLITE_OK]. ^If an error** code is returned, that error will propagate back up through the** SQLite code base to cause the statement that provoked the callback** to report an error, though the commit will have still occurred. If the** callback returns [SQLITE_ROW] or [SQLITE_DONE], or if it returns a value** that does not correspond to any valid SQLite error code, the results** are undefined.**** A single database handle may have at most a single write-ahead log callback ** registered at one time. ^Calling [sqlite3_wal_hook()] replaces any** previously registered write-ahead log callback. ^Note that the** [sqlite3_wal_autocheckpoint()] interface and the** [wal_autocheckpoint pragma] both invoke [sqlite3_wal_hook()] and will** overwrite any prior [sqlite3_wal_hook()] settings.*/SQLITE_APIvoid*sqlite3_wal_hook(sqlite3*,int(*)(void*,sqlite3*,constchar*,int),void*);/*** CAPI3REF: Configure an auto-checkpoint** METHOD: sqlite3**** ^The [sqlite3_wal_autocheckpoint(D,N)] is a wrapper around** [sqlite3_wal_hook()] that causes any database on [database connection] D** to automatically [checkpoint]** after committing a transaction if there are N or** more frames in the [write-ahead log] file. ^Passing zero or ** a negative value as the nFrame parameter disables automatic** checkpoints entirely.**** ^The callback registered by this function replaces any existing callback** registered using [sqlite3_wal_hook()]. ^Likewise, registering a callback** using [sqlite3_wal_hook()] disables the automatic checkpoint mechanism** configured by this function.**** ^The [wal_autocheckpoint pragma] can be used to invoke this interface** from SQL.**** ^Checkpoints initiated by this mechanism are** [sqlite3_wal_checkpoint_v2|PASSIVE].**** ^Every new [database connection] defaults to having the auto-checkpoint** enabled with a threshold of 1000 or [SQLITE_DEFAULT_WAL_AUTOCHECKPOINT]** pages. The use of this interface** is only necessary if the default setting is found to be suboptimal** for a particular application.*/SQLITE_APIintsqlite3_wal_autocheckpoint(sqlite3*db,intN);/*** CAPI3REF: Checkpoint a database** METHOD: sqlite3**** ^(The sqlite3_wal_checkpoint(D,X) is equivalent to** [sqlite3_wal_checkpoint_v2](D,X,[SQLITE_CHECKPOINT_PASSIVE],0,0).)^**** In brief, sqlite3_wal_checkpoint(D,X) causes the content in the ** [write-ahead log] for database X on [database connection] D to be** transferred into the database file and for the write-ahead log to** be reset. See the [checkpointing] documentation for addition** information.**** This interface used to be the only way to cause a checkpoint to** occur. But then the newer and more powerful [sqlite3_wal_checkpoint_v2()]** interface was added. This interface is retained for backwards** compatibility and as a convenience for applications that need to manually** start a callback but which do not need the full power (and corresponding** complication) of [sqlite3_wal_checkpoint_v2()].*/SQLITE_APIintsqlite3_wal_checkpoint(sqlite3*db,constchar*zDb);/*** CAPI3REF: Checkpoint a database** METHOD: sqlite3**** ^(The sqlite3_wal_checkpoint_v2(D,X,M,L,C) interface runs a checkpoint** operation on database X of [database connection] D in mode M. Status** information is written back into integers pointed to by L and C.)^** ^(The M parameter must be a valid [checkpoint mode]:)^**** <dl>** <dt>SQLITE_CHECKPOINT_PASSIVE<dd>** ^Checkpoint as many frames as possible without waiting for any database ** readers or writers to finish, then sync the database file if all frames ** in the log were checkpointed. ^The [busy-handler callback]** is never invoked in the SQLITE_CHECKPOINT_PASSIVE mode. ** ^On the other hand, passive mode might leave the checkpoint unfinished** if there are concurrent readers or writers.**** <dt>SQLITE_CHECKPOINT_FULL<dd>** ^This mode blocks (it invokes the** [sqlite3_busy_handler|busy-handler callback]) until there is no** database writer and all readers are reading from the most recent database** snapshot. ^It then checkpoints all frames in the log file and syncs the** database file. ^This mode blocks new database writers while it is pending,** but new database readers are allowed to continue unimpeded.**** <dt>SQLITE_CHECKPOINT_RESTART<dd>** ^This mode works the same way as SQLITE_CHECKPOINT_FULL with the addition** that after checkpointing the log file it blocks (calls the ** [busy-handler callback])** until all readers are reading from the database file only. ^This ensures ** that the next writer will restart the log file from the beginning.** ^Like SQLITE_CHECKPOINT_FULL, this mode blocks new** database writer attempts while it is pending, but does not impede readers.**** <dt>SQLITE_CHECKPOINT_TRUNCATE<dd>** ^This mode works the same way as SQLITE_CHECKPOINT_RESTART with the** addition that it also truncates the log file to zero bytes just prior** to a successful return.** </dl>**** ^If pnLog is not NULL, then *pnLog is set to the total number of frames in** the log file or to -1 if the checkpoint could not run because** of an error or because the database is not in [WAL mode]. ^If pnCkpt is not** NULL,then *pnCkpt is set to the total number of checkpointed frames in the** log file (including any that were already checkpointed before the function** was called) or to -1 if the checkpoint could not run due to an error or** because the database is not in WAL mode. ^Note that upon successful** completion of an SQLITE_CHECKPOINT_TRUNCATE, the log file will have been** truncated to zero bytes and so both *pnLog and *pnCkpt will be set to zero.**** ^All calls obtain an exclusive "checkpoint" lock on the database file. ^If** any other process is running a checkpoint operation at the same time, the ** lock cannot be obtained and SQLITE_BUSY is returned. ^Even if there is a ** busy-handler configured, it will not be invoked in this case.**** ^The SQLITE_CHECKPOINT_FULL, RESTART and TRUNCATE modes also obtain the ** exclusive "writer" lock on the database file. ^If the writer lock cannot be** obtained immediately, and a busy-handler is configured, it is invoked and** the writer lock retried until either the busy-handler returns 0 or the lock** is successfully obtained. ^The busy-handler is also invoked while waiting for** database readers as described above. ^If the busy-handler returns 0 before** the writer lock is obtained or while waiting for database readers, the** checkpoint operation proceeds from that point in the same way as ** SQLITE_CHECKPOINT_PASSIVE - checkpointing as many frames as possible ** without blocking any further. ^SQLITE_BUSY is returned in this case.**** ^If parameter zDb is NULL or points to a zero length string, then the** specified operation is attempted on all WAL databases [attached] to ** [database connection] db. In this case the** values written to output parameters *pnLog and *pnCkpt are undefined. ^If ** an SQLITE_BUSY error is encountered when processing one or more of the ** attached WAL databases, the operation is still attempted on any remaining ** attached databases and SQLITE_BUSY is returned at the end. ^If any other ** error occurs while processing an attached database, processing is abandoned ** and the error code is returned to the caller immediately. ^If no error ** (SQLITE_BUSY or otherwise) is encountered while processing the attached ** databases, SQLITE_OK is returned.**** ^If database zDb is the name of an attached database that is not in WAL** mode, SQLITE_OK is returned and both *pnLog and *pnCkpt set to -1. ^If** zDb is not NULL (or a zero length string) and is not the name of any** attached database, SQLITE_ERROR is returned to the caller.**** ^Unless it returns SQLITE_MISUSE,** the sqlite3_wal_checkpoint_v2() interface** sets the error information that is queried by** [sqlite3_errcode()] and [sqlite3_errmsg()].**** ^The [PRAGMA wal_checkpoint] command can be used to invoke this interface** from SQL.*/SQLITE_APIintsqlite3_wal_checkpoint_v2(sqlite3*db,/* Database handle */constchar*zDb,/* Name of attached database (or NULL) */inteMode,/* SQLITE_CHECKPOINT_* value */int*pnLog,/* OUT: Size of WAL log in frames */int*pnCkpt/* OUT: Total number of frames checkpointed */);/*** CAPI3REF: Checkpoint Mode Values** KEYWORDS: {checkpoint mode}**** These constants define all valid values for the "checkpoint mode" passed** as the third parameter to the [sqlite3_wal_checkpoint_v2()] interface.** See the [sqlite3_wal_checkpoint_v2()] documentation for details on the** meaning of each of these checkpoint modes.*/#define SQLITE_CHECKPOINT_PASSIVE 0 /* Do as much as possible w/o blocking */#define SQLITE_CHECKPOINT_FULL 1 /* Wait for writers, then checkpoint */#define SQLITE_CHECKPOINT_RESTART 2 /* Like FULL but wait for for readers */#define SQLITE_CHECKPOINT_TRUNCATE 3 /* Like RESTART but also truncate WAL *//*** CAPI3REF: Virtual Table Interface Configuration**** This function may be called by either the [xConnect] or [xCreate] method** of a [virtual table] implementation to configure** various facets of the virtual table interface.**** If this interface is invoked outside the context of an xConnect or** xCreate virtual table method then the behavior is undefined.**** At present, there is only one option that may be configured using** this function. (See [SQLITE_VTAB_CONSTRAINT_SUPPORT].) Further options** may be added in the future.*/SQLITE_APIintsqlite3_vtab_config(sqlite3*,intop,...);/*** CAPI3REF: Virtual Table Configuration Options**** These macros define the various options to the** [sqlite3_vtab_config()] interface that [virtual table] implementations** can use to customize and optimize their behavior.**** <dl>** <dt>SQLITE_VTAB_CONSTRAINT_SUPPORT** <dd>Calls of the form** [sqlite3_vtab_config](db,SQLITE_VTAB_CONSTRAINT_SUPPORT,X) are supported,** where X is an integer. If X is zero, then the [virtual table] whose** [xCreate] or [xConnect] method invoked [sqlite3_vtab_config()] does not** support constraints. In this configuration (which is the default) if** a call to the [xUpdate] method returns [SQLITE_CONSTRAINT], then the entire** statement is rolled back as if [ON CONFLICT | OR ABORT] had been** specified as part of the users SQL statement, regardless of the actual** ON CONFLICT mode specified.**** If X is non-zero, then the virtual table implementation guarantees** that if [xUpdate] returns [SQLITE_CONSTRAINT], it will do so before** any modifications to internal or persistent data structures have been made.** If the [ON CONFLICT] mode is ABORT, FAIL, IGNORE or ROLLBACK, SQLite ** is able to roll back a statement or database transaction, and abandon** or continue processing the current SQL statement as appropriate. ** If the ON CONFLICT mode is REPLACE and the [xUpdate] method returns** [SQLITE_CONSTRAINT], SQLite handles this as if the ON CONFLICT mode** had been ABORT.**** Virtual table implementations that are required to handle OR REPLACE** must do so within the [xUpdate] method. If a call to the ** [sqlite3_vtab_on_conflict()] function indicates that the current ON ** CONFLICT policy is REPLACE, the virtual table implementation should ** silently replace the appropriate rows within the xUpdate callback and** return SQLITE_OK. Or, if this is not possible, it may return** SQLITE_CONSTRAINT, in which case SQLite falls back to OR ABORT ** constraint handling.** </dl>*/#define SQLITE_VTAB_CONSTRAINT_SUPPORT 1/*** CAPI3REF: Determine The Virtual Table Conflict Policy**** This function may only be called from within a call to the [xUpdate] method** of a [virtual table] implementation for an INSERT or UPDATE operation. ^The** value returned is one of [SQLITE_ROLLBACK], [SQLITE_IGNORE], [SQLITE_FAIL],** [SQLITE_ABORT], or [SQLITE_REPLACE], according to the [ON CONFLICT] mode** of the SQL statement that triggered the call to the [xUpdate] method of the** [virtual table].*/SQLITE_APIintsqlite3_vtab_on_conflict(sqlite3*);/*** CAPI3REF: Conflict resolution modes** KEYWORDS: {conflict resolution mode}**** These constants are returned by [sqlite3_vtab_on_conflict()] to** inform a [virtual table] implementation what the [ON CONFLICT] mode** is for the SQL statement being evaluated.**** Note that the [SQLITE_IGNORE] constant is also used as a potential** return value from the [sqlite3_set_authorizer()] callback and that** [SQLITE_ABORT] is also a [result code].*/#define SQLITE_ROLLBACK 1/* #define SQLITE_IGNORE 2 // Also used by sqlite3_authorizer() callback */#define SQLITE_FAIL 3/* #define SQLITE_ABORT 4 // Also an error code */#define SQLITE_REPLACE 5/*** CAPI3REF: Prepared Statement Scan Status Opcodes** KEYWORDS: {scanstatus options}**** The following constants can be used for the T parameter to the** [sqlite3_stmt_scanstatus(S,X,T,V)] interface. Each constant designates a** different metric for sqlite3_stmt_scanstatus() to return.**** When the value returned to V is a string, space to hold that string is** managed by the prepared statement S and will be automatically freed when** S is finalized.**** <dl>** [[SQLITE_SCANSTAT_NLOOP]] <dt>SQLITE_SCANSTAT_NLOOP</dt>** <dd>^The [sqlite3_int64] variable pointed to by the T parameter will be** set to the total number of times that the X-th loop has run.</dd>**** [[SQLITE_SCANSTAT_NVISIT]] <dt>SQLITE_SCANSTAT_NVISIT</dt>** <dd>^The [sqlite3_int64] variable pointed to by the T parameter will be set** to the total number of rows examined by all iterations of the X-th loop.</dd>**** [[SQLITE_SCANSTAT_EST]] <dt>SQLITE_SCANSTAT_EST</dt>** <dd>^The "double" variable pointed to by the T parameter will be set to the** query planner's estimate for the average number of rows output from each** iteration of the X-th loop. If the query planner's estimates was accurate,** then this value will approximate the quotient NVISIT/NLOOP and the** product of this value for all prior loops with the same SELECTID will** be the NLOOP value for the current loop.**** [[SQLITE_SCANSTAT_NAME]] <dt>SQLITE_SCANSTAT_NAME</dt>** <dd>^The "const char *" variable pointed to by the T parameter will be set** to a zero-terminated UTF-8 string containing the name of the index or table** used for the X-th loop.**** [[SQLITE_SCANSTAT_EXPLAIN]] <dt>SQLITE_SCANSTAT_EXPLAIN</dt>** <dd>^The "const char *" variable pointed to by the T parameter will be set** to a zero-terminated UTF-8 string containing the [EXPLAIN QUERY PLAN]** description for the X-th loop.**** [[SQLITE_SCANSTAT_SELECTID]] <dt>SQLITE_SCANSTAT_SELECT</dt>** <dd>^The "int" variable pointed to by the T parameter will be set to the** "select-id" for the X-th loop. The select-id identifies which query or** subquery the loop is part of. The main query has a select-id of zero.** The select-id is the same value as is output in the first column** of an [EXPLAIN QUERY PLAN] query.** </dl>*/#define SQLITE_SCANSTAT_NLOOP 0#define SQLITE_SCANSTAT_NVISIT 1#define SQLITE_SCANSTAT_EST 2#define SQLITE_SCANSTAT_NAME 3#define SQLITE_SCANSTAT_EXPLAIN 4#define SQLITE_SCANSTAT_SELECTID 5/*** CAPI3REF: Prepared Statement Scan Status** METHOD: sqlite3_stmt**** This interface returns information about the predicted and measured** performance for pStmt. Advanced applications can use this** interface to compare the predicted and the measured performance and** issue warnings and/or rerun [ANALYZE] if discrepancies are found.**** Since this interface is expected to be rarely used, it is only** available if SQLite is compiled using the [SQLITE_ENABLE_STMT_SCANSTATUS]** compile-time option.**** The "iScanStatusOp" parameter determines which status information to return.** The "iScanStatusOp" must be one of the [scanstatus options] or the behavior** of this interface is undefined.** ^The requested measurement is written into a variable pointed to by** the "pOut" parameter.** Parameter "idx" identifies the specific loop to retrieve statistics for.** Loops are numbered starting from zero. ^If idx is out of range - less than** zero or greater than or equal to the total number of loops used to implement** the statement - a non-zero value is returned and the variable that pOut** points to is unchanged.**** ^Statistics might not be available for all loops in all statements. ^In cases** where there exist loops with no available statistics, this function behaves** as if the loop did not exist - it returns non-zero and leave the variable** that pOut points to unchanged.**** See also: [sqlite3_stmt_scanstatus_reset()]*/SQLITE_APIintsqlite3_stmt_scanstatus(sqlite3_stmt*pStmt,/* Prepared statement for which info desired */intidx,/* Index of loop to report on */intiScanStatusOp,/* Information desired. SQLITE_SCANSTAT_* */void*pOut/* Result written here */);/*** CAPI3REF: Zero Scan-Status Counters** METHOD: sqlite3_stmt**** ^Zero all [sqlite3_stmt_scanstatus()] related event counters.**** This API is only available if the library is built with pre-processor** symbol [SQLITE_ENABLE_STMT_SCANSTATUS] defined.*/SQLITE_APIvoidsqlite3_stmt_scanstatus_reset(sqlite3_stmt*);/*** CAPI3REF: Flush caches to disk mid-transaction**** ^If a write-transaction is open on [database connection] D when the** [sqlite3_db_cacheflush(D)] interface invoked, any dirty** pages in the pager-cache that are not currently in use are written out ** to disk. A dirty page may be in use if a database cursor created by an** active SQL statement is reading from it, or if it is page 1 of a database** file (page 1 is always "in use"). ^The [sqlite3_db_cacheflush(D)]** interface flushes caches for all schemas - "main", "temp", and** any [attached] databases.**** ^If this function needs to obtain extra database locks before dirty pages ** can be flushed to disk, it does so. ^If those locks cannot be obtained ** immediately and there is a busy-handler callback configured, it is invoked** in the usual manner. ^If the required lock still cannot be obtained, then** the database is skipped and an attempt made to flush any dirty pages** belonging to the next (if any) database. ^If any databases are skipped** because locks cannot be obtained, but no other error occurs, this** function returns SQLITE_BUSY.**** ^If any other error occurs while flushing dirty pages to disk (for** example an IO error or out-of-memory condition), then processing is** abandoned and an SQLite [error code] is returned to the caller immediately.**** ^Otherwise, if no error occurs, [sqlite3_db_cacheflush()] returns SQLITE_OK.**** ^This function does not set the database handle error code or message** returned by the [sqlite3_errcode()] and [sqlite3_errmsg()] functions.*/SQLITE_APIintsqlite3_db_cacheflush(sqlite3*);/*** CAPI3REF: The pre-update hook.**** ^These interfaces are only available if SQLite is compiled using the** [SQLITE_ENABLE_PREUPDATE_HOOK] compile-time option.**** ^The [sqlite3_preupdate_hook()] interface registers a callback function** that is invoked prior to each [INSERT], [UPDATE], and [DELETE] operation** on a [rowid table].** ^At most one preupdate hook may be registered at a time on a single** [database connection]; each call to [sqlite3_preupdate_hook()] overrides** the previous setting.** ^The preupdate hook is disabled by invoking [sqlite3_preupdate_hook()]** with a NULL pointer as the second parameter.** ^The third parameter to [sqlite3_preupdate_hook()] is passed through as** the first parameter to callbacks.**** ^The preupdate hook only fires for changes to [rowid tables]; the preupdate** hook is not invoked for changes to [virtual tables] or [WITHOUT ROWID]** tables.**** ^The second parameter to the preupdate callback is a pointer to** the [database connection] that registered the preupdate hook.** ^The third parameter to the preupdate callback is one of the constants** [SQLITE_INSERT], [SQLITE_DELETE], or [SQLITE_UPDATE] to identify the** kind of update operation that is about to occur.** ^(The fourth parameter to the preupdate callback is the name of the** database within the database connection that is being modified. This** will be "main" for the main database or "temp" for TEMP tables or ** the name given after the AS keyword in the [ATTACH] statement for attached** databases.)^** ^The fifth parameter to the preupdate callback is the name of the** table that is being modified.** ^The sixth parameter to the preupdate callback is the initial [rowid] of the** row being changes for SQLITE_UPDATE and SQLITE_DELETE changes and is** undefined for SQLITE_INSERT changes.** ^The seventh parameter to the preupdate callback is the final [rowid] of** the row being changed for SQLITE_UPDATE and SQLITE_INSERT changes and is** undefined for SQLITE_DELETE changes.**** The [sqlite3_preupdate_old()], [sqlite3_preupdate_new()],** [sqlite3_preupdate_count()], and [sqlite3_preupdate_depth()] interfaces** provide additional information about a preupdate event. These routines** may only be called from within a preupdate callback. Invoking any of** these routines from outside of a preupdate callback or with a** [database connection] pointer that is different from the one supplied** to the preupdate callback results in undefined and probably undesirable** behavior.**** ^The [sqlite3_preupdate_count(D)] interface returns the number of columns** in the row that is being inserted, updated, or deleted.**** ^The [sqlite3_preupdate_old(D,N,P)] interface writes into P a pointer to** a [protected sqlite3_value] that contains the value of the Nth column of** the table row before it is updated. The N parameter must be between 0** and one less than the number of columns or the behavior will be** undefined. This must only be used within SQLITE_UPDATE and SQLITE_DELETE** preupdate callbacks; if it is used by an SQLITE_INSERT callback then the** behavior is undefined. The [sqlite3_value] that P points to** will be destroyed when the preupdate callback returns.**** ^The [sqlite3_preupdate_new(D,N,P)] interface writes into P a pointer to** a [protected sqlite3_value] that contains the value of the Nth column of** the table row after it is updated. The N parameter must be between 0** and one less than the number of columns or the behavior will be** undefined. This must only be used within SQLITE_INSERT and SQLITE_UPDATE** preupdate callbacks; if it is used by an SQLITE_DELETE callback then the** behavior is undefined. The [sqlite3_value] that P points to** will be destroyed when the preupdate callback returns.**** ^The [sqlite3_preupdate_depth(D)] interface returns 0 if the preupdate** callback was invoked as a result of a direct insert, update, or delete** operation; or 1 for inserts, updates, or deletes invoked by top-level ** triggers; or 2 for changes resulting from triggers called by top-level** triggers; and so forth.**** See also: [sqlite3_update_hook()]*/SQLITE_APISQLITE_EXPERIMENTALvoid*sqlite3_preupdate_hook(sqlite3*db,void(*xPreUpdate)(void*pCtx,/* Copy of third arg to preupdate_hook() */sqlite3*db,/* Database handle */intop,/* SQLITE_UPDATE, DELETE or INSERT */charconst*zDb,/* Database name */charconst*zName,/* Table name */sqlite3_int64iKey1,/* Rowid of row about to be deleted/updated */sqlite3_int64iKey2/* New rowid value (for a rowid UPDATE) */),void*);SQLITE_APISQLITE_EXPERIMENTALintsqlite3_preupdate_old(sqlite3*,int,sqlite3_value**);SQLITE_APISQLITE_EXPERIMENTALintsqlite3_preupdate_count(sqlite3*);SQLITE_APISQLITE_EXPERIMENTALintsqlite3_preupdate_depth(sqlite3*);SQLITE_APISQLITE_EXPERIMENTALintsqlite3_preupdate_new(sqlite3*,int,sqlite3_value**);/*** CAPI3REF: Low-level system error code**** ^Attempt to return the underlying operating system error code or error** number that caused the most recent I/O error or failure to open a file.** The return value is OS-dependent. For example, on unix systems, after** [sqlite3_open_v2()] returns [SQLITE_CANTOPEN], this interface could be** called to get back the underlying "errno" that caused the problem, such** as ENOSPC, EAUTH, EISDIR, and so forth. */SQLITE_APIintsqlite3_system_errno(sqlite3*);/*** CAPI3REF: Database Snapshot** KEYWORDS: {snapshot}** EXPERIMENTAL**** An instance of the snapshot object records the state of a [WAL mode]** database for some specific point in history.**** In [WAL mode], multiple [database connections] that are open on the** same database file can each be reading a different historical version** of the database file. When a [database connection] begins a read** transaction, that connection sees an unchanging copy of the database** as it existed for the point in time when the transaction first started.** Subsequent changes to the database from other connections are not seen** by the reader until a new read transaction is started.**** The sqlite3_snapshot object records state information about an historical** version of the database file so that it is possible to later open a new read** transaction that sees that historical version of the database rather than** the most recent version.**** The constructor for this object is [sqlite3_snapshot_get()]. The** [sqlite3_snapshot_open()] method causes a fresh read transaction to refer** to an historical snapshot (if possible). The destructor for ** sqlite3_snapshot objects is [sqlite3_snapshot_free()].*/typedefstructsqlite3_snapshotsqlite3_snapshot;/*** CAPI3REF: Record A Database Snapshot** EXPERIMENTAL**** ^The [sqlite3_snapshot_get(D,S,P)] interface attempts to make a** new [sqlite3_snapshot] object that records the current state of** schema S in database connection D. ^On success, the** [sqlite3_snapshot_get(D,S,P)] interface writes a pointer to the newly** created [sqlite3_snapshot] object into *P and returns SQLITE_OK.** ^If schema S of [database connection] D is not a [WAL mode] database** that is in a read transaction, then [sqlite3_snapshot_get(D,S,P)]** leaves the *P value unchanged and returns an appropriate [error code].**** The [sqlite3_snapshot] object returned from a successful call to** [sqlite3_snapshot_get()] must be freed using [sqlite3_snapshot_free()]** to avoid a memory leak.**** The [sqlite3_snapshot_get()] interface is only available when the** SQLITE_ENABLE_SNAPSHOT compile-time option is used.*/SQLITE_APISQLITE_EXPERIMENTALintsqlite3_snapshot_get(sqlite3*db,constchar*zSchema,sqlite3_snapshot**ppSnapshot);/*** CAPI3REF: Start a read transaction on an historical snapshot** EXPERIMENTAL**** ^The [sqlite3_snapshot_open(D,S,P)] interface starts a** read transaction for schema S of** [database connection] D such that the read transaction** refers to historical [snapshot] P, rather than the most** recent change to the database.** ^The [sqlite3_snapshot_open()] interface returns SQLITE_OK on success** or an appropriate [error code] if it fails.**** ^In order to succeed, a call to [sqlite3_snapshot_open(D,S,P)] must be** the first operation following the [BEGIN] that takes the schema S** out of [autocommit mode].** ^In other words, schema S must not currently be in** a transaction for [sqlite3_snapshot_open(D,S,P)] to work, but the** database connection D must be out of [autocommit mode].** ^A [snapshot] will fail to open if it has been overwritten by a** [checkpoint].** ^(A call to [sqlite3_snapshot_open(D,S,P)] will fail if the** database connection D does not know that the database file for** schema S is in [WAL mode]. A database connection might not know** that the database file is in [WAL mode] if there has been no prior** I/O on that database connection, or if the database entered [WAL mode] ** after the most recent I/O on the database connection.)^** (Hint: Run "[PRAGMA application_id]" against a newly opened** database connection in order to make it ready to use snapshots.)**** The [sqlite3_snapshot_open()] interface is only available when the** SQLITE_ENABLE_SNAPSHOT compile-time option is used.*/SQLITE_APISQLITE_EXPERIMENTALintsqlite3_snapshot_open(sqlite3*db,constchar*zSchema,sqlite3_snapshot*pSnapshot);/*** CAPI3REF: Destroy a snapshot** EXPERIMENTAL**** ^The [sqlite3_snapshot_free(P)] interface destroys [sqlite3_snapshot] P.** The application must eventually free every [sqlite3_snapshot] object** using this routine to avoid a memory leak.**** The [sqlite3_snapshot_free()] interface is only available when the** SQLITE_ENABLE_SNAPSHOT compile-time option is used.*/SQLITE_APISQLITE_EXPERIMENTALvoidsqlite3_snapshot_free(sqlite3_snapshot*);/*** CAPI3REF: Compare the ages of two snapshot handles.** EXPERIMENTAL**** The sqlite3_snapshot_cmp(P1, P2) interface is used to compare the ages** of two valid snapshot handles. **** If the two snapshot handles are not associated with the same database ** file, the result of the comparison is undefined. **** Additionally, the result of the comparison is only valid if both of the** snapshot handles were obtained by calling sqlite3_snapshot_get() since the** last time the wal file was deleted. The wal file is deleted when the** database is changed back to rollback mode or when the number of database** clients drops to zero. If either snapshot handle was obtained before the ** wal file was last deleted, the value returned by this function ** is undefined.**** Otherwise, this API returns a negative value if P1 refers to an older** snapshot than P2, zero if the two handles refer to the same database** snapshot, and a positive value if P1 is a newer snapshot than P2.*/SQLITE_APISQLITE_EXPERIMENTALintsqlite3_snapshot_cmp(sqlite3_snapshot*p1,sqlite3_snapshot*p2);/*** Undo the hack that converts floating point types to integer for** builds on processors without floating point support.*/#ifdef SQLITE_OMIT_FLOATING_POINT# undef double#endif#ifdef __cplusplus}/* End of the 'extern "C"' block */#endif#endif /* SQLITE3_H *//******** Begin file sqlite3rtree.h *********//*** 2010 August 30**** The author disclaims copyright to this source code. In place of** a legal notice, here is a blessing:**** May you do good and not evil.** May you find forgiveness for yourself and forgive others.** May you share freely, never taking more than you give.****************************************************************************/#ifndef _SQLITE3RTREE_H_#define _SQLITE3RTREE_H_#ifdef __cplusplusextern"C"{#endiftypedefstructsqlite3_rtree_geometrysqlite3_rtree_geometry;typedefstructsqlite3_rtree_query_infosqlite3_rtree_query_info;/* The double-precision datatype used by RTree depends on the** SQLITE_RTREE_INT_ONLY compile-time option.*/#ifdef SQLITE_RTREE_INT_ONLYtypedefsqlite3_int64sqlite3_rtree_dbl;#elsetypedefdoublesqlite3_rtree_dbl;#endif/*** Register a geometry callback named zGeom that can be used as part of an** R-Tree geometry query as follows:**** SELECT ... FROM <rtree> WHERE <rtree col> MATCH $zGeom(... params ...)*/SQLITE_APIintsqlite3_rtree_geometry_callback(sqlite3*db,constchar*zGeom,int(*xGeom)(sqlite3_rtree_geometry*,int,sqlite3_rtree_dbl*,int*),void*pContext);/*** A pointer to a structure of the following type is passed as the first** argument to callbacks registered using rtree_geometry_callback().*/structsqlite3_rtree_geometry{void*pContext;/* Copy of pContext passed to s_r_g_c() */intnParam;/* Size of array aParam[] */sqlite3_rtree_dbl*aParam;/* Parameters passed to SQL geom function */void*pUser;/* Callback implementation user data */void(*xDelUser)(void*);/* Called by SQLite to clean up pUser */};/*** Register a 2nd-generation geometry callback named zScore that can be ** used as part of an R-Tree geometry query as follows:**** SELECT ... FROM <rtree> WHERE <rtree col> MATCH $zQueryFunc(... params ...)*/SQLITE_APIintsqlite3_rtree_query_callback(sqlite3*db,constchar*zQueryFunc,int(*xQueryFunc)(sqlite3_rtree_query_info*),void*pContext,void(*xDestructor)(void*));/*** A pointer to a structure of the following type is passed as the ** argument to scored geometry callback registered using** sqlite3_rtree_query_callback().**** Note that the first 5 fields of this structure are identical to** sqlite3_rtree_geometry. This structure is a subclass of** sqlite3_rtree_geometry.*/structsqlite3_rtree_query_info{void*pContext;/* pContext from when function registered */intnParam;/* Number of function parameters */sqlite3_rtree_dbl*aParam;/* value of function parameters */void*pUser;/* callback can use this, if desired */void(*xDelUser)(void*);/* function to free pUser */sqlite3_rtree_dbl*aCoord;/* Coordinates of node or entry to check */unsignedint*anQueue;/* Number of pending entries in the queue */intnCoord;/* Number of coordinates */intiLevel;/* Level of current node or entry */intmxLevel;/* The largest iLevel value in the tree */sqlite3_int64iRowid;/* Rowid for current entry */sqlite3_rtree_dblrParentScore;/* Score of parent node */inteParentWithin;/* Visibility of parent node */inteWithin;/* OUT: Visiblity */sqlite3_rtree_dblrScore;/* OUT: Write the score here *//* The following fields are only available in 3.8.11 and later */sqlite3_value**apSqlParam;/* Original SQL values of parameters */};/*** Allowed values for sqlite3_rtree_query.eWithin and .eParentWithin.*/#define NOT_WITHIN 0 /* Object completely outside of query region */#define PARTLY_WITHIN 1 /* Object partially overlaps query region */#define FULLY_WITHIN 2 /* Object fully contained within query region */#ifdef __cplusplus}/* end of the 'extern "C"' block */#endif#endif /* ifndef _SQLITE3RTREE_H_ *//******** End of sqlite3rtree.h *********//******** Begin file sqlite3session.h *********/#if !defined(__SQLITESESSION_H_) && defined(SQLITE_ENABLE_SESSION)#define __SQLITESESSION_H_ 1/*** Make sure we can call this stuff from C++.*/#ifdef __cplusplusextern"C"{#endif/*** CAPI3REF: Session Object Handle*/typedefstructsqlite3_sessionsqlite3_session;/*** CAPI3REF: Changeset Iterator Handle*/typedefstructsqlite3_changeset_itersqlite3_changeset_iter;/*** CAPI3REF: Create A New Session Object**** Create a new session object attached to database handle db. If successful,** a pointer to the new object is written to *ppSession and SQLITE_OK is** returned. If an error occurs, *ppSession is set to NULL and an SQLite** error code (e.g. SQLITE_NOMEM) is returned.**** It is possible to create multiple session objects attached to a single** database handle.**** Session objects created using this function should be deleted using the** [sqlite3session_delete()] function before the database handle that they** are attached to is itself closed. If the database handle is closed before** the session object is deleted, then the results of calling any session** module function, including [sqlite3session_delete()] on the session object** are undefined.**** Because the session module uses the [sqlite3_preupdate_hook()] API, it** is not possible for an application to register a pre-update hook on a** database handle that has one or more session objects attached. Nor is** it possible to create a session object attached to a database handle for** which a pre-update hook is already defined. The results of attempting ** either of these things are undefined.**** The session object will be used to create changesets for tables in** database zDb, where zDb is either "main", or "temp", or the name of an** attached database. It is not an error if database zDb is not attached** to the database when the session object is created.*/intsqlite3session_create(sqlite3*db,/* Database handle */constchar*zDb,/* Name of db (e.g. "main") */sqlite3_session**ppSession/* OUT: New session object */);/*** CAPI3REF: Delete A Session Object**** Delete a session object previously allocated using ** [sqlite3session_create()]. Once a session object has been deleted, the** results of attempting to use pSession with any other session module** function are undefined.**** Session objects must be deleted before the database handle to which they** are attached is closed. Refer to the documentation for ** [sqlite3session_create()] for details.*/voidsqlite3session_delete(sqlite3_session*pSession);/*** CAPI3REF: Enable Or Disable A Session Object**** Enable or disable the recording of changes by a session object. When** enabled, a session object records changes made to the database. When** disabled - it does not. A newly created session object is enabled.** Refer to the documentation for [sqlite3session_changeset()] for further** details regarding how enabling and disabling a session object affects** the eventual changesets.**** Passing zero to this function disables the session. Passing a value** greater than zero enables it. Passing a value less than zero is a ** no-op, and may be used to query the current state of the session.**** The return value indicates the final state of the session object: 0 if ** the session is disabled, or 1 if it is enabled.*/intsqlite3session_enable(sqlite3_session*pSession,intbEnable);/*** CAPI3REF: Set Or Clear the Indirect Change Flag**** Each change recorded by a session object is marked as either direct or** indirect. A change is marked as indirect if either:**** <ul>** <li> The session object "indirect" flag is set when the change is** made, or** <li> The change is made by an SQL trigger or foreign key action ** instead of directly as a result of a users SQL statement.** </ul>**** If a single row is affected by more than one operation within a session,** then the change is considered indirect if all operations meet the criteria** for an indirect change above, or direct otherwise.**** This function is used to set, clear or query the session object indirect** flag. If the second argument passed to this function is zero, then the** indirect flag is cleared. If it is greater than zero, the indirect flag** is set. Passing a value less than zero does not modify the current value** of the indirect flag, and may be used to query the current state of the ** indirect flag for the specified session object.**** The return value indicates the final state of the indirect flag: 0 if ** it is clear, or 1 if it is set.*/intsqlite3session_indirect(sqlite3_session*pSession,intbIndirect);/*** CAPI3REF: Attach A Table To A Session Object**** If argument zTab is not NULL, then it is the name of a table to attach** to the session object passed as the first argument. All subsequent changes ** made to the table while the session object is enabled will be recorded. See ** documentation for [sqlite3session_changeset()] for further details.**** Or, if argument zTab is NULL, then changes are recorded for all tables** in the database. If additional tables are added to the database (by ** executing "CREATE TABLE" statements) after this call is made, changes for ** the new tables are also recorded.**** Changes can only be recorded for tables that have a PRIMARY KEY explicitly** defined as part of their CREATE TABLE statement. It does not matter if the ** PRIMARY KEY is an "INTEGER PRIMARY KEY" (rowid alias) or not. The PRIMARY** KEY may consist of a single column, or may be a composite key.** ** It is not an error if the named table does not exist in the database. Nor** is it an error if the named table does not have a PRIMARY KEY. However,** no changes will be recorded in either of these scenarios.**** Changes are not recorded for individual rows that have NULL values stored** in one or more of their PRIMARY KEY columns.**** SQLITE_OK is returned if the call completes without error. Or, if an error ** occurs, an SQLite error code (e.g. SQLITE_NOMEM) is returned.*/intsqlite3session_attach(sqlite3_session*pSession,/* Session object */constchar*zTab/* Table name */);/*** CAPI3REF: Set a table filter on a Session Object.**** The second argument (xFilter) is the "filter callback". For changes to rows ** in tables that are not attached to the Session object, the filter is called** to determine whether changes to the table's rows should be tracked or not. ** If xFilter returns 0, changes is not tracked. Note that once a table is ** attached, xFilter will not be called again.*/voidsqlite3session_table_filter(sqlite3_session*pSession,/* Session object */int(*xFilter)(void*pCtx,/* Copy of third arg to _filter_table() */constchar*zTab/* Table name */),void*pCtx/* First argument passed to xFilter */);/*** CAPI3REF: Generate A Changeset From A Session Object**** Obtain a changeset containing changes to the tables attached to the ** session object passed as the first argument. If successful, ** set *ppChangeset to point to a buffer containing the changeset ** and *pnChangeset to the size of the changeset in bytes before returning** SQLITE_OK. If an error occurs, set both *ppChangeset and *pnChangeset to** zero and return an SQLite error code.**** A changeset consists of zero or more INSERT, UPDATE and/or DELETE changes,** each representing a change to a single row of an attached table. An INSERT** change contains the values of each field of a new database row. A DELETE** contains the original values of each field of a deleted database row. An** UPDATE change contains the original values of each field of an updated** database row along with the updated values for each updated non-primary-key** column. It is not possible for an UPDATE change to represent a change that** modifies the values of primary key columns. If such a change is made, it** is represented in a changeset as a DELETE followed by an INSERT.**** Changes are not recorded for rows that have NULL values stored in one or ** more of their PRIMARY KEY columns. If such a row is inserted or deleted,** no corresponding change is present in the changesets returned by this** function. If an existing row with one or more NULL values stored in** PRIMARY KEY columns is updated so that all PRIMARY KEY columns are non-NULL,** only an INSERT is appears in the changeset. Similarly, if an existing row** with non-NULL PRIMARY KEY values is updated so that one or more of its** PRIMARY KEY columns are set to NULL, the resulting changeset contains a** DELETE change only.**** The contents of a changeset may be traversed using an iterator created** using the [sqlite3changeset_start()] API. A changeset may be applied to** a database with a compatible schema using the [sqlite3changeset_apply()]** API.**** Within a changeset generated by this function, all changes related to a** single table are grouped together. In other words, when iterating through** a changeset or when applying a changeset to a database, all changes related** to a single table are processed before moving on to the next table. Tables** are sorted in the same order in which they were attached (or auto-attached)** to the sqlite3_session object. The order in which the changes related to** a single table are stored is undefined.**** Following a successful call to this function, it is the responsibility of** the caller to eventually free the buffer that *ppChangeset points to using** [sqlite3_free()].**** <h3>Changeset Generation</h3>**** Once a table has been attached to a session object, the session object** records the primary key values of all new rows inserted into the table.** It also records the original primary key and other column values of any** deleted or updated rows. For each unique primary key value, data is only** recorded once - the first time a row with said primary key is inserted,** updated or deleted in the lifetime of the session.**** There is one exception to the previous paragraph: when a row is inserted,** updated or deleted, if one or more of its primary key columns contain a** NULL value, no record of the change is made.**** The session object therefore accumulates two types of records - those** that consist of primary key values only (created when the user inserts** a new record) and those that consist of the primary key values and the** original values of other table columns (created when the users deletes** or updates a record).**** When this function is called, the requested changeset is created using** both the accumulated records and the current contents of the database** file. Specifically:**** <ul>** <li> For each record generated by an insert, the database is queried** for a row with a matching primary key. If one is found, an INSERT** change is added to the changeset. If no such row is found, no change ** is added to the changeset.**** <li> For each record generated by an update or delete, the database is ** queried for a row with a matching primary key. If such a row is** found and one or more of the non-primary key fields have been** modified from their original values, an UPDATE change is added to ** the changeset. Or, if no such row is found in the table, a DELETE ** change is added to the changeset. If there is a row with a matching** primary key in the database, but all fields contain their original** values, no change is added to the changeset.** </ul>**** This means, amongst other things, that if a row is inserted and then later** deleted while a session object is active, neither the insert nor the delete** will be present in the changeset. Or if a row is deleted and then later a ** row with the same primary key values inserted while a session object is** active, the resulting changeset will contain an UPDATE change instead of** a DELETE and an INSERT.**** When a session object is disabled (see the [sqlite3session_enable()] API),** it does not accumulate records when rows are inserted, updated or deleted.** This may appear to have some counter-intuitive effects if a single row** is written to more than once during a session. For example, if a row** is inserted while a session object is enabled, then later deleted while ** the same session object is disabled, no INSERT record will appear in the** changeset, even though the delete took place while the session was disabled.** Or, if one field of a row is updated while a session is disabled, and ** another field of the same row is updated while the session is enabled, the** resulting changeset will contain an UPDATE change that updates both fields.*/intsqlite3session_changeset(sqlite3_session*pSession,/* Session object */int*pnChangeset,/* OUT: Size of buffer at *ppChangeset */void**ppChangeset/* OUT: Buffer containing changeset */);/*** CAPI3REF: Load The Difference Between Tables Into A Session **** If it is not already attached to the session object passed as the first** argument, this function attaches table zTbl in the same manner as the** [sqlite3session_attach()] function. If zTbl does not exist, or if it** does not have a primary key, this function is a no-op (but does not return** an error).**** Argument zFromDb must be the name of a database ("main", "temp" etc.)** attached to the same database handle as the session object that contains ** a table compatible with the table attached to the session by this function.** A table is considered compatible if it:**** <ul>** <li> Has the same name,** <li> Has the same set of columns declared in the same order, and** <li> Has the same PRIMARY KEY definition.** </ul>**** If the tables are not compatible, SQLITE_SCHEMA is returned. If the tables** are compatible but do not have any PRIMARY KEY columns, it is not an error** but no changes are added to the session object. As with other session** APIs, tables without PRIMARY KEYs are simply ignored.**** This function adds a set of changes to the session object that could be** used to update the table in database zFrom (call this the "from-table") ** so that its content is the same as the table attached to the session ** object (call this the "to-table"). Specifically:**** <ul>** <li> For each row (primary key) that exists in the to-table but not in ** the from-table, an INSERT record is added to the session object.**** <li> For each row (primary key) that exists in the to-table but not in ** the from-table, a DELETE record is added to the session object.**** <li> For each row (primary key) that exists in both tables, but features ** different in each, an UPDATE record is added to the session.** </ul>**** To clarify, if this function is called and then a changeset constructed** using [sqlite3session_changeset()], then after applying that changeset to ** database zFrom the contents of the two compatible tables would be ** identical.**** It an error if database zFrom does not exist or does not contain the** required compatible table.**** If the operation successful, SQLITE_OK is returned. Otherwise, an SQLite** error code. In this case, if argument pzErrMsg is not NULL, *pzErrMsg** may be set to point to a buffer containing an English language error ** message. It is the responsibility of the caller to free this buffer using** sqlite3_free().*/intsqlite3session_diff(sqlite3_session*pSession,constchar*zFromDb,constchar*zTbl,char**pzErrMsg);/*** CAPI3REF: Generate A Patchset From A Session Object**** The differences between a patchset and a changeset are that:**** <ul>** <li> DELETE records consist of the primary key fields only. The ** original values of other fields are omitted.** <li> The original values of any modified fields are omitted from ** UPDATE records.** </ul>**** A patchset blob may be used with up to date versions of all ** sqlite3changeset_xxx API functions except for sqlite3changeset_invert(), ** which returns SQLITE_CORRUPT if it is passed a patchset. Similarly,** attempting to use a patchset blob with old versions of the** sqlite3changeset_xxx APIs also provokes an SQLITE_CORRUPT error. **** Because the non-primary key "old.*" fields are omitted, no ** SQLITE_CHANGESET_DATA conflicts can be detected or reported if a patchset** is passed to the sqlite3changeset_apply() API. Other conflict types work** in the same way as for changesets.**** Changes within a patchset are ordered in the same way as for changesets** generated by the sqlite3session_changeset() function (i.e. all changes for** a single table are grouped together, tables appear in the order in which** they were attached to the session object).*/intsqlite3session_patchset(sqlite3_session*pSession,/* Session object */int*pnPatchset,/* OUT: Size of buffer at *ppChangeset */void**ppPatchset/* OUT: Buffer containing changeset */);/*** CAPI3REF: Test if a changeset has recorded any changes.**** Return non-zero if no changes to attached tables have been recorded by ** the session object passed as the first argument. Otherwise, if one or ** more changes have been recorded, return zero.**** Even if this function returns zero, it is possible that calling** [sqlite3session_changeset()] on the session handle may still return a** changeset that contains no changes. This can happen when a row in ** an attached table is modified and then later on the original values ** are restored. However, if this function returns non-zero, then it is** guaranteed that a call to sqlite3session_changeset() will return a ** changeset containing zero changes.*/intsqlite3session_isempty(sqlite3_session*pSession);/*** CAPI3REF: Create An Iterator To Traverse A Changeset **** Create an iterator used to iterate through the contents of a changeset.** If successful, *pp is set to point to the iterator handle and SQLITE_OK** is returned. Otherwise, if an error occurs, *pp is set to zero and an** SQLite error code is returned.**** The following functions can be used to advance and query a changeset ** iterator created by this function:**** <ul>** <li> [sqlite3changeset_next()]** <li> [sqlite3changeset_op()]** <li> [sqlite3changeset_new()]** <li> [sqlite3changeset_old()]** </ul>**** It is the responsibility of the caller to eventually destroy the iterator** by passing it to [sqlite3changeset_finalize()]. The buffer containing the** changeset (pChangeset) must remain valid until after the iterator is** destroyed.**** Assuming the changeset blob was created by one of the** [sqlite3session_changeset()], [sqlite3changeset_concat()] or** [sqlite3changeset_invert()] functions, all changes within the changeset ** that apply to a single table are grouped together. This means that when ** an application iterates through a changeset using an iterator created by ** this function, all changes that relate to a single table are visited ** consecutively. There is no chance that the iterator will visit a change ** the applies to table X, then one for table Y, and then later on visit ** another change for table X.*/intsqlite3changeset_start(sqlite3_changeset_iter**pp,/* OUT: New changeset iterator handle */intnChangeset,/* Size of changeset blob in bytes */void*pChangeset/* Pointer to blob containing changeset */);/*** CAPI3REF: Advance A Changeset Iterator**** This function may only be used with iterators created by function** [sqlite3changeset_start()]. If it is called on an iterator passed to** a conflict-handler callback by [sqlite3changeset_apply()], SQLITE_MISUSE** is returned and the call has no effect.**** Immediately after an iterator is created by sqlite3changeset_start(), it** does not point to any change in the changeset. Assuming the changeset** is not empty, the first call to this function advances the iterator to** point to the first change in the changeset. Each subsequent call advances** the iterator to point to the next change in the changeset (if any). If** no error occurs and the iterator points to a valid change after a call** to sqlite3changeset_next() has advanced it, SQLITE_ROW is returned. ** Otherwise, if all changes in the changeset have already been visited,** SQLITE_DONE is returned.**** If an error occurs, an SQLite error code is returned. Possible error ** codes include SQLITE_CORRUPT (if the changeset buffer is corrupt) or ** SQLITE_NOMEM.*/intsqlite3changeset_next(sqlite3_changeset_iter*pIter);/*** CAPI3REF: Obtain The Current Operation From A Changeset Iterator**** The pIter argument passed to this function may either be an iterator** passed to a conflict-handler by [sqlite3changeset_apply()], or an iterator** created by [sqlite3changeset_start()]. In the latter case, the most recent** call to [sqlite3changeset_next()] must have returned [SQLITE_ROW]. If this** is not the case, this function returns [SQLITE_MISUSE].**** If argument pzTab is not NULL, then *pzTab is set to point to a** nul-terminated utf-8 encoded string containing the name of the table** affected by the current change. The buffer remains valid until either** sqlite3changeset_next() is called on the iterator or until the ** conflict-handler function returns. If pnCol is not NULL, then *pnCol is ** set to the number of columns in the table affected by the change. If** pbIncorrect is not NULL, then *pbIndirect is set to true (1) if the change** is an indirect change, or false (0) otherwise. See the documentation for** [sqlite3session_indirect()] for a description of direct and indirect** changes. Finally, if pOp is not NULL, then *pOp is set to one of ** [SQLITE_INSERT], [SQLITE_DELETE] or [SQLITE_UPDATE], depending on the ** type of change that the iterator currently points to.**** If no error occurs, SQLITE_OK is returned. If an error does occur, an** SQLite error code is returned. The values of the output variables may not** be trusted in this case.*/intsqlite3changeset_op(sqlite3_changeset_iter*pIter,/* Iterator object */constchar**pzTab,/* OUT: Pointer to table name */int*pnCol,/* OUT: Number of columns in table */int*pOp,/* OUT: SQLITE_INSERT, DELETE or UPDATE */int*pbIndirect/* OUT: True for an 'indirect' change */);/*** CAPI3REF: Obtain The Primary Key Definition Of A Table**** For each modified table, a changeset includes the following:**** <ul>** <li> The number of columns in the table, and** <li> Which of those columns make up the tables PRIMARY KEY.** </ul>**** This function is used to find which columns comprise the PRIMARY KEY of** the table modified by the change that iterator pIter currently points to.** If successful, *pabPK is set to point to an array of nCol entries, where** nCol is the number of columns in the table. Elements of *pabPK are set to** 0x01 if the corresponding column is part of the tables primary key, or** 0x00 if it is not.**** If argument pnCol is not NULL, then *pnCol is set to the number of columns** in the table.**** If this function is called when the iterator does not point to a valid** entry, SQLITE_MISUSE is returned and the output variables zeroed. Otherwise,** SQLITE_OK is returned and the output variables populated as described** above.*/intsqlite3changeset_pk(sqlite3_changeset_iter*pIter,/* Iterator object */unsignedchar**pabPK,/* OUT: Array of boolean - true for PK cols */int*pnCol/* OUT: Number of entries in output array */);/*** CAPI3REF: Obtain old.* Values From A Changeset Iterator**** The pIter argument passed to this function may either be an iterator** passed to a conflict-handler by [sqlite3changeset_apply()], or an iterator** created by [sqlite3changeset_start()]. In the latter case, the most recent** call to [sqlite3changeset_next()] must have returned SQLITE_ROW. ** Furthermore, it may only be called if the type of change that the iterator** currently points to is either [SQLITE_DELETE] or [SQLITE_UPDATE]. Otherwise,** this function returns [SQLITE_MISUSE] and sets *ppValue to NULL.**** Argument iVal must be greater than or equal to 0, and less than the number** of columns in the table affected by the current change. Otherwise,** [SQLITE_RANGE] is returned and *ppValue is set to NULL.**** If successful, this function sets *ppValue to point to a protected** sqlite3_value object containing the iVal'th value from the vector of ** original row values stored as part of the UPDATE or DELETE change and** returns SQLITE_OK. The name of the function comes from the fact that this ** is similar to the "old.*" columns available to update or delete triggers.**** If some other error occurs (e.g. an OOM condition), an SQLite error code** is returned and *ppValue is set to NULL.*/intsqlite3changeset_old(sqlite3_changeset_iter*pIter,/* Changeset iterator */intiVal,/* Column number */sqlite3_value**ppValue/* OUT: Old value (or NULL pointer) */);/*** CAPI3REF: Obtain new.* Values From A Changeset Iterator**** The pIter argument passed to this function may either be an iterator** passed to a conflict-handler by [sqlite3changeset_apply()], or an iterator** created by [sqlite3changeset_start()]. In the latter case, the most recent** call to [sqlite3changeset_next()] must have returned SQLITE_ROW. ** Furthermore, it may only be called if the type of change that the iterator** currently points to is either [SQLITE_UPDATE] or [SQLITE_INSERT]. Otherwise,** this function returns [SQLITE_MISUSE] and sets *ppValue to NULL.**** Argument iVal must be greater than or equal to 0, and less than the number** of columns in the table affected by the current change. Otherwise,** [SQLITE_RANGE] is returned and *ppValue is set to NULL.**** If successful, this function sets *ppValue to point to a protected** sqlite3_value object containing the iVal'th value from the vector of ** new row values stored as part of the UPDATE or INSERT change and** returns SQLITE_OK. If the change is an UPDATE and does not include** a new value for the requested column, *ppValue is set to NULL and ** SQLITE_OK returned. The name of the function comes from the fact that ** this is similar to the "new.*" columns available to update or delete ** triggers.**** If some other error occurs (e.g. an OOM condition), an SQLite error code** is returned and *ppValue is set to NULL.*/intsqlite3changeset_new(sqlite3_changeset_iter*pIter,/* Changeset iterator */intiVal,/* Column number */sqlite3_value**ppValue/* OUT: New value (or NULL pointer) */);/*** CAPI3REF: Obtain Conflicting Row Values From A Changeset Iterator**** This function should only be used with iterator objects passed to a** conflict-handler callback by [sqlite3changeset_apply()] with either** [SQLITE_CHANGESET_DATA] or [SQLITE_CHANGESET_CONFLICT]. If this function** is called on any other iterator, [SQLITE_MISUSE] is returned and *ppValue** is set to NULL.**** Argument iVal must be greater than or equal to 0, and less than the number** of columns in the table affected by the current change. Otherwise,** [SQLITE_RANGE] is returned and *ppValue is set to NULL.**** If successful, this function sets *ppValue to point to a protected** sqlite3_value object containing the iVal'th value from the ** "conflicting row" associated with the current conflict-handler callback** and returns SQLITE_OK.**** If some other error occurs (e.g. an OOM condition), an SQLite error code** is returned and *ppValue is set to NULL.*/intsqlite3changeset_conflict(sqlite3_changeset_iter*pIter,/* Changeset iterator */intiVal,/* Column number */sqlite3_value**ppValue/* OUT: Value from conflicting row */);/*** CAPI3REF: Determine The Number Of Foreign Key Constraint Violations**** This function may only be called with an iterator passed to an** SQLITE_CHANGESET_FOREIGN_KEY conflict handler callback. In this case** it sets the output variable to the total number of known foreign key** violations in the destination database and returns SQLITE_OK.**** In all other cases this function returns SQLITE_MISUSE.*/intsqlite3changeset_fk_conflicts(sqlite3_changeset_iter*pIter,/* Changeset iterator */int*pnOut/* OUT: Number of FK violations */);/*** CAPI3REF: Finalize A Changeset Iterator**** This function is used to finalize an iterator allocated with** [sqlite3changeset_start()].**** This function should only be called on iterators created using the** [sqlite3changeset_start()] function. If an application calls this** function with an iterator passed to a conflict-handler by** [sqlite3changeset_apply()], [SQLITE_MISUSE] is immediately returned and the** call has no effect.**** If an error was encountered within a call to an sqlite3changeset_xxx()** function (for example an [SQLITE_CORRUPT] in [sqlite3changeset_next()] or an ** [SQLITE_NOMEM] in [sqlite3changeset_new()]) then an error code corresponding** to that error is returned by this function. Otherwise, SQLITE_OK is** returned. This is to allow the following pattern (pseudo-code):**** sqlite3changeset_start();** while( SQLITE_ROW==sqlite3changeset_next() ){** // Do something with change.** }** rc = sqlite3changeset_finalize();** if( rc!=SQLITE_OK ){** // An error has occurred ** }*/intsqlite3changeset_finalize(sqlite3_changeset_iter*pIter);/*** CAPI3REF: Invert A Changeset**** This function is used to "invert" a changeset object. Applying an inverted** changeset to a database reverses the effects of applying the uninverted** changeset. Specifically:**** <ul>** <li> Each DELETE change is changed to an INSERT, and** <li> Each INSERT change is changed to a DELETE, and** <li> For each UPDATE change, the old.* and new.* values are exchanged.** </ul>**** This function does not change the order in which changes appear within** the changeset. It merely reverses the sense of each individual change.**** If successful, a pointer to a buffer containing the inverted changeset** is stored in *ppOut, the size of the same buffer is stored in *pnOut, and** SQLITE_OK is returned. If an error occurs, both *pnOut and *ppOut are** zeroed and an SQLite error code returned.**** It is the responsibility of the caller to eventually call sqlite3_free()** on the *ppOut pointer to free the buffer allocation following a successful ** call to this function.**** WARNING/TODO: This function currently assumes that the input is a valid** changeset. If it is not, the results are undefined.*/intsqlite3changeset_invert(intnIn,constvoid*pIn,/* Input changeset */int*pnOut,void**ppOut/* OUT: Inverse of input */);/*** CAPI3REF: Concatenate Two Changeset Objects**** This function is used to concatenate two changesets, A and B, into a ** single changeset. The result is a changeset equivalent to applying** changeset A followed by changeset B. **** This function combines the two input changesets using an ** sqlite3_changegroup object. Calling it produces similar results as the** following code fragment:**** sqlite3_changegroup *pGrp;** rc = sqlite3_changegroup_new(&pGrp);** if( rc==SQLITE_OK ) rc = sqlite3changegroup_add(pGrp, nA, pA);** if( rc==SQLITE_OK ) rc = sqlite3changegroup_add(pGrp, nB, pB);** if( rc==SQLITE_OK ){** rc = sqlite3changegroup_output(pGrp, pnOut, ppOut);** }else{** *ppOut = 0;** *pnOut = 0;** }**** Refer to the sqlite3_changegroup documentation below for details.*/intsqlite3changeset_concat(intnA,/* Number of bytes in buffer pA */void*pA,/* Pointer to buffer containing changeset A */intnB,/* Number of bytes in buffer pB */void*pB,/* Pointer to buffer containing changeset B */int*pnOut,/* OUT: Number of bytes in output changeset */void**ppOut/* OUT: Buffer containing output changeset */);/*** CAPI3REF: Changegroup Handle*/typedefstructsqlite3_changegroupsqlite3_changegroup;/*** CAPI3REF: Create A New Changegroup Object**** An sqlite3_changegroup object is used to combine two or more changesets** (or patchsets) into a single changeset (or patchset). A single changegroup** object may combine changesets or patchsets, but not both. The output is** always in the same format as the input.**** If successful, this function returns SQLITE_OK and populates (*pp) with** a pointer to a new sqlite3_changegroup object before returning. The caller** should eventually free the returned object using a call to ** sqlite3changegroup_delete(). If an error occurs, an SQLite error code** (i.e. SQLITE_NOMEM) is returned and *pp is set to NULL.**** The usual usage pattern for an sqlite3_changegroup object is as follows:**** <ul>** <li> It is created using a call to sqlite3changegroup_new().**** <li> Zero or more changesets (or patchsets) are added to the object** by calling sqlite3changegroup_add().**** <li> The result of combining all input changesets together is obtained ** by the application via a call to sqlite3changegroup_output().**** <li> The object is deleted using a call to sqlite3changegroup_delete().** </ul>**** Any number of calls to add() and output() may be made between the calls to** new() and delete(), and in any order.**** As well as the regular sqlite3changegroup_add() and ** sqlite3changegroup_output() functions, also available are the streaming** versions sqlite3changegroup_add_strm() and sqlite3changegroup_output_strm().*/intsqlite3changegroup_new(sqlite3_changegroup**pp);/*** CAPI3REF: Add A Changeset To A Changegroup**** Add all changes within the changeset (or patchset) in buffer pData (size** nData bytes) to the changegroup. **** If the buffer contains a patchset, then all prior calls to this function** on the same changegroup object must also have specified patchsets. Or, if** the buffer contains a changeset, so must have the earlier calls to this** function. Otherwise, SQLITE_ERROR is returned and no changes are added** to the changegroup.**** Rows within the changeset and changegroup are identified by the values in** their PRIMARY KEY columns. A change in the changeset is considered to** apply to the same row as a change already present in the changegroup if** the two rows have the same primary key.**** Changes to rows that do not already appear in the changegroup are** simply copied into it. Or, if both the new changeset and the changegroup** contain changes that apply to a single row, the final contents of the** changegroup depends on the type of each change, as follows:**** <table border=1 style="margin-left:8ex;margin-right:8ex">** <tr><th style="white-space:pre">Existing Change </th>** <th style="white-space:pre">New Change </th>** <th>Output Change** <tr><td>INSERT <td>INSERT <td>** The new change is ignored. This case does not occur if the new** changeset was recorded immediately after the changesets already** added to the changegroup.** <tr><td>INSERT <td>UPDATE <td>** The INSERT change remains in the changegroup. The values in the ** INSERT change are modified as if the row was inserted by the** existing change and then updated according to the new change.** <tr><td>INSERT <td>DELETE <td>** The existing INSERT is removed from the changegroup. The DELETE is** not added.** <tr><td>UPDATE <td>INSERT <td>** The new change is ignored. This case does not occur if the new** changeset was recorded immediately after the changesets already** added to the changegroup.** <tr><td>UPDATE <td>UPDATE <td>** The existing UPDATE remains within the changegroup. It is amended ** so that the accompanying values are as if the row was updated once ** by the existing change and then again by the new change.** <tr><td>UPDATE <td>DELETE <td>** The existing UPDATE is replaced by the new DELETE within the** changegroup.** <tr><td>DELETE <td>INSERT <td>** If one or more of the column values in the row inserted by the** new change differ from those in the row deleted by the existing ** change, the existing DELETE is replaced by an UPDATE within the** changegroup. Otherwise, if the inserted row is exactly the same ** as the deleted row, the existing DELETE is simply discarded.** <tr><td>DELETE <td>UPDATE <td>** The new change is ignored. This case does not occur if the new** changeset was recorded immediately after the changesets already** added to the changegroup.** <tr><td>DELETE <td>DELETE <td>** The new change is ignored. This case does not occur if the new** changeset was recorded immediately after the changesets already** added to the changegroup.** </table>**** If the new changeset contains changes to a table that is already present** in the changegroup, then the number of columns and the position of the** primary key columns for the table must be consistent. If this is not the** case, this function fails with SQLITE_SCHEMA. If the input changeset** appears to be corrupt and the corruption is detected, SQLITE_CORRUPT is** returned. Or, if an out-of-memory condition occurs during processing, this** function returns SQLITE_NOMEM. In all cases, if an error occurs the** final contents of the changegroup is undefined.**** If no error occurs, SQLITE_OK is returned.*/intsqlite3changegroup_add(sqlite3_changegroup*,intnData,void*pData);/*** CAPI3REF: Obtain A Composite Changeset From A Changegroup**** Obtain a buffer containing a changeset (or patchset) representing the** current contents of the changegroup. If the inputs to the changegroup** were themselves changesets, the output is a changeset. Or, if the** inputs were patchsets, the output is also a patchset.**** As with the output of the sqlite3session_changeset() and** sqlite3session_patchset() functions, all changes related to a single** table are grouped together in the output of this function. Tables appear** in the same order as for the very first changeset added to the changegroup.** If the second or subsequent changesets added to the changegroup contain** changes for tables that do not appear in the first changeset, they are** appended onto the end of the output changeset, again in the order in** which they are first encountered.**** If an error occurs, an SQLite error code is returned and the output** variables (*pnData) and (*ppData) are set to 0. Otherwise, SQLITE_OK** is returned and the output variables are set to the size of and a ** pointer to the output buffer, respectively. In this case it is the** responsibility of the caller to eventually free the buffer using a** call to sqlite3_free().*/intsqlite3changegroup_output(sqlite3_changegroup*,int*pnData,/* OUT: Size of output buffer in bytes */void**ppData/* OUT: Pointer to output buffer */);/*** CAPI3REF: Delete A Changegroup Object*/voidsqlite3changegroup_delete(sqlite3_changegroup*);/*** CAPI3REF: Apply A Changeset To A Database**** Apply a changeset to a database. This function attempts to update the** "main" database attached to handle db with the changes found in the** changeset passed via the second and third arguments.**** The fourth argument (xFilter) passed to this function is the "filter** callback". If it is not NULL, then for each table affected by at least one** change in the changeset, the filter callback is invoked with** the table name as the second argument, and a copy of the context pointer** passed as the sixth argument to this function as the first. If the "filter** callback" returns zero, then no attempt is made to apply any changes to ** the table. Otherwise, if the return value is non-zero or the xFilter** argument to this function is NULL, all changes related to the table are** attempted.**** For each table that is not excluded by the filter callback, this function ** tests that the target database contains a compatible table. A table is ** considered compatible if all of the following are true:**** <ul>** <li> The table has the same name as the name recorded in the ** changeset, and** <li> The table has the same number of columns as recorded in the ** changeset, and** <li> The table has primary key columns in the same position as ** recorded in the changeset.** </ul>**** If there is no compatible table, it is not an error, but none of the** changes associated with the table are applied. A warning message is issued** via the sqlite3_log() mechanism with the error code SQLITE_SCHEMA. At most** one such warning is issued for each table in the changeset.**** For each change for which there is a compatible table, an attempt is made ** to modify the table contents according to the UPDATE, INSERT or DELETE ** change. If a change cannot be applied cleanly, the conflict handler ** function passed as the fifth argument to sqlite3changeset_apply() may be ** invoked. A description of exactly when the conflict handler is invoked for ** each type of change is below.**** Unlike the xFilter argument, xConflict may not be passed NULL. The results** of passing anything other than a valid function pointer as the xConflict** argument are undefined.**** Each time the conflict handler function is invoked, it must return one** of [SQLITE_CHANGESET_OMIT], [SQLITE_CHANGESET_ABORT] or ** [SQLITE_CHANGESET_REPLACE]. SQLITE_CHANGESET_REPLACE may only be returned** if the second argument passed to the conflict handler is either** SQLITE_CHANGESET_DATA or SQLITE_CHANGESET_CONFLICT. If the conflict-handler** returns an illegal value, any changes already made are rolled back and** the call to sqlite3changeset_apply() returns SQLITE_MISUSE. Different ** actions are taken by sqlite3changeset_apply() depending on the value** returned by each invocation of the conflict-handler function. Refer to** the documentation for the three ** [SQLITE_CHANGESET_OMIT|available return values] for details.**** <dl>** <dt>DELETE Changes<dd>** For each DELETE change, this function checks if the target database ** contains a row with the same primary key value (or values) as the ** original row values stored in the changeset. If it does, and the values ** stored in all non-primary key columns also match the values stored in ** the changeset the row is deleted from the target database.**** If a row with matching primary key values is found, but one or more of** the non-primary key fields contains a value different from the original** row value stored in the changeset, the conflict-handler function is** invoked with [SQLITE_CHANGESET_DATA] as the second argument.**** If no row with matching primary key values is found in the database,** the conflict-handler function is invoked with [SQLITE_CHANGESET_NOTFOUND]** passed as the second argument.**** If the DELETE operation is attempted, but SQLite returns SQLITE_CONSTRAINT** (which can only happen if a foreign key constraint is violated), the** conflict-handler function is invoked with [SQLITE_CHANGESET_CONSTRAINT]** passed as the second argument. This includes the case where the DELETE** operation is attempted because an earlier call to the conflict handler** function returned [SQLITE_CHANGESET_REPLACE].**** <dt>INSERT Changes<dd>** For each INSERT change, an attempt is made to insert the new row into** the database.**** If the attempt to insert the row fails because the database already ** contains a row with the same primary key values, the conflict handler** function is invoked with the second argument set to ** [SQLITE_CHANGESET_CONFLICT].**** If the attempt to insert the row fails because of some other constraint** violation (e.g. NOT NULL or UNIQUE), the conflict handler function is ** invoked with the second argument set to [SQLITE_CHANGESET_CONSTRAINT].** This includes the case where the INSERT operation is re-attempted because ** an earlier call to the conflict handler function returned ** [SQLITE_CHANGESET_REPLACE].**** <dt>UPDATE Changes<dd>** For each UPDATE change, this function checks if the target database ** contains a row with the same primary key value (or values) as the ** original row values stored in the changeset. If it does, and the values ** stored in all non-primary key columns also match the values stored in ** the changeset the row is updated within the target database.**** If a row with matching primary key values is found, but one or more of** the non-primary key fields contains a value different from an original** row value stored in the changeset, the conflict-handler function is** invoked with [SQLITE_CHANGESET_DATA] as the second argument. Since** UPDATE changes only contain values for non-primary key fields that are** to be modified, only those fields need to match the original values to** avoid the SQLITE_CHANGESET_DATA conflict-handler callback.**** If no row with matching primary key values is found in the database,** the conflict-handler function is invoked with [SQLITE_CHANGESET_NOTFOUND]** passed as the second argument.**** If the UPDATE operation is attempted, but SQLite returns ** SQLITE_CONSTRAINT, the conflict-handler function is invoked with ** [SQLITE_CHANGESET_CONSTRAINT] passed as the second argument.** This includes the case where the UPDATE operation is attempted after ** an earlier call to the conflict handler function returned** [SQLITE_CHANGESET_REPLACE]. ** </dl>**** It is safe to execute SQL statements, including those that write to the** table that the callback related to, from within the xConflict callback.** This can be used to further customize the applications conflict** resolution strategy.**** All changes made by this function are enclosed in a savepoint transaction.** If any other error (aside from a constraint failure when attempting to** write to the target database) occurs, then the savepoint transaction is** rolled back, restoring the target database to its original state, and an ** SQLite error code returned.*/intsqlite3changeset_apply(sqlite3*db,/* Apply change to "main" db of this handle */intnChangeset,/* Size of changeset in bytes */void*pChangeset,/* Changeset blob */int(*xFilter)(void*pCtx,/* Copy of sixth arg to _apply() */constchar*zTab/* Table name */),int(*xConflict)(void*pCtx,/* Copy of sixth arg to _apply() */inteConflict,/* DATA, MISSING, CONFLICT, CONSTRAINT */sqlite3_changeset_iter*p/* Handle describing change and conflict */),void*pCtx/* First argument passed to xConflict */);/* ** CAPI3REF: Constants Passed To The Conflict Handler**** Values that may be passed as the second argument to a conflict-handler.**** <dl>** <dt>SQLITE_CHANGESET_DATA<dd>** The conflict handler is invoked with CHANGESET_DATA as the second argument** when processing a DELETE or UPDATE change if a row with the required** PRIMARY KEY fields is present in the database, but one or more other ** (non primary-key) fields modified by the update do not contain the ** expected "before" values.** ** The conflicting row, in this case, is the database row with the matching** primary key.** ** <dt>SQLITE_CHANGESET_NOTFOUND<dd>** The conflict handler is invoked with CHANGESET_NOTFOUND as the second** argument when processing a DELETE or UPDATE change if a row with the** required PRIMARY KEY fields is not present in the database.** ** There is no conflicting row in this case. The results of invoking the** sqlite3changeset_conflict() API are undefined.** ** <dt>SQLITE_CHANGESET_CONFLICT<dd>** CHANGESET_CONFLICT is passed as the second argument to the conflict** handler while processing an INSERT change if the operation would result ** in duplicate primary key values.** ** The conflicting row in this case is the database row with the matching** primary key.**** <dt>SQLITE_CHANGESET_FOREIGN_KEY<dd>** If foreign key handling is enabled, and applying a changeset leaves the** database in a state containing foreign key violations, the conflict ** handler is invoked with CHANGESET_FOREIGN_KEY as the second argument** exactly once before the changeset is committed. If the conflict handler** returns CHANGESET_OMIT, the changes, including those that caused the** foreign key constraint violation, are committed. Or, if it returns** CHANGESET_ABORT, the changeset is rolled back.**** No current or conflicting row information is provided. The only function** it is possible to call on the supplied sqlite3_changeset_iter handle** is sqlite3changeset_fk_conflicts().** ** <dt>SQLITE_CHANGESET_CONSTRAINT<dd>** If any other constraint violation occurs while applying a change (i.e. ** a UNIQUE, CHECK or NOT NULL constraint), the conflict handler is ** invoked with CHANGESET_CONSTRAINT as the second argument.** ** There is no conflicting row in this case. The results of invoking the** sqlite3changeset_conflict() API are undefined.**** </dl>*/#define SQLITE_CHANGESET_DATA 1#define SQLITE_CHANGESET_NOTFOUND 2#define SQLITE_CHANGESET_CONFLICT 3#define SQLITE_CHANGESET_CONSTRAINT 4#define SQLITE_CHANGESET_FOREIGN_KEY 5/* ** CAPI3REF: Constants Returned By The Conflict Handler**** A conflict handler callback must return one of the following three values.**** <dl>** <dt>SQLITE_CHANGESET_OMIT<dd>** If a conflict handler returns this value no special action is taken. The** change that caused the conflict is not applied. The session module ** continues to the next change in the changeset.**** <dt>SQLITE_CHANGESET_REPLACE<dd>** This value may only be returned if the second argument to the conflict** handler was SQLITE_CHANGESET_DATA or SQLITE_CHANGESET_CONFLICT. If this** is not the case, any changes applied so far are rolled back and the ** call to sqlite3changeset_apply() returns SQLITE_MISUSE.**** If CHANGESET_REPLACE is returned by an SQLITE_CHANGESET_DATA conflict** handler, then the conflicting row is either updated or deleted, depending** on the type of change.**** If CHANGESET_REPLACE is returned by an SQLITE_CHANGESET_CONFLICT conflict** handler, then the conflicting row is removed from the database and a** second attempt to apply the change is made. If this second attempt fails,** the original row is restored to the database before continuing.**** <dt>SQLITE_CHANGESET_ABORT<dd>** If this value is returned, any changes applied so far are rolled back ** and the call to sqlite3changeset_apply() returns SQLITE_ABORT.** </dl>*/#define SQLITE_CHANGESET_OMIT 0#define SQLITE_CHANGESET_REPLACE 1#define SQLITE_CHANGESET_ABORT 2/*** CAPI3REF: Streaming Versions of API functions.**** The six streaming API xxx_strm() functions serve similar purposes to the ** corresponding non-streaming API functions:**** <table border=1 style="margin-left:8ex;margin-right:8ex">** <tr><th>Streaming function<th>Non-streaming equivalent</th>** <tr><td>sqlite3changeset_apply_str<td>[sqlite3changeset_apply] ** <tr><td>sqlite3changeset_concat_str<td>[sqlite3changeset_concat] ** <tr><td>sqlite3changeset_invert_str<td>[sqlite3changeset_invert] ** <tr><td>sqlite3changeset_start_str<td>[sqlite3changeset_start] ** <tr><td>sqlite3session_changeset_str<td>[sqlite3session_changeset] ** <tr><td>sqlite3session_patchset_str<td>[sqlite3session_patchset] ** </table>**** Non-streaming functions that accept changesets (or patchsets) as input** require that the entire changeset be stored in a single buffer in memory. ** Similarly, those that return a changeset or patchset do so by returning ** a pointer to a single large buffer allocated using sqlite3_malloc(). ** Normally this is convenient. However, if an application running in a ** low-memory environment is required to handle very large changesets, the** large contiguous memory allocations required can become onerous.**** In order to avoid this problem, instead of a single large buffer, input** is passed to a streaming API functions by way of a callback function that** the sessions module invokes to incrementally request input data as it is** required. In all cases, a pair of API function parameters such as**** <pre>** int nChangeset,** void *pChangeset,** </pre>**** Is replaced by:**** <pre>** int (*xInput)(void *pIn, void *pData, int *pnData),** void *pIn,** </pre>**** Each time the xInput callback is invoked by the sessions module, the first** argument passed is a copy of the supplied pIn context pointer. The second ** argument, pData, points to a buffer (*pnData) bytes in size. Assuming no ** error occurs the xInput method should copy up to (*pnData) bytes of data ** into the buffer and set (*pnData) to the actual number of bytes copied ** before returning SQLITE_OK. If the input is completely exhausted, (*pnData) ** should be set to zero to indicate this. Or, if an error occurs, an SQLite ** error code should be returned. In all cases, if an xInput callback returns** an error, all processing is abandoned and the streaming API function** returns a copy of the error code to the caller.**** In the case of sqlite3changeset_start_strm(), the xInput callback may be** invoked by the sessions module at any point during the lifetime of the** iterator. If such an xInput callback returns an error, the iterator enters** an error state, whereby all subsequent calls to iterator functions ** immediately fail with the same error code as returned by xInput.**** Similarly, streaming API functions that return changesets (or patchsets)** return them in chunks by way of a callback function instead of via a** pointer to a single large buffer. In this case, a pair of parameters such** as:**** <pre>** int *pnChangeset,** void **ppChangeset,** </pre>**** Is replaced by:**** <pre>** int (*xOutput)(void *pOut, const void *pData, int nData),** void *pOut** </pre>**** The xOutput callback is invoked zero or more times to return data to** the application. The first parameter passed to each call is a copy of the** pOut pointer supplied by the application. The second parameter, pData,** points to a buffer nData bytes in size containing the chunk of output** data being returned. If the xOutput callback successfully processes the** supplied data, it should return SQLITE_OK to indicate success. Otherwise,** it should return some other SQLite error code. In this case processing** is immediately abandoned and the streaming API function returns a copy** of the xOutput error code to the application.**** The sessions module never invokes an xOutput callback with the third ** parameter set to a value less than or equal to zero. Other than this,** no guarantees are made as to the size of the chunks of data returned.*/intsqlite3changeset_apply_strm(sqlite3*db,/* Apply change to "main" db of this handle */int(*xInput)(void*pIn,void*pData,int*pnData),/* Input function */void*pIn,/* First arg for xInput */int(*xFilter)(void*pCtx,/* Copy of sixth arg to _apply() */constchar*zTab/* Table name */),int(*xConflict)(void*pCtx,/* Copy of sixth arg to _apply() */inteConflict,/* DATA, MISSING, CONFLICT, CONSTRAINT */sqlite3_changeset_iter*p/* Handle describing change and conflict */),void*pCtx/* First argument passed to xConflict */);intsqlite3changeset_concat_strm(int(*xInputA)(void*pIn,void*pData,int*pnData),void*pInA,int(*xInputB)(void*pIn,void*pData,int*pnData),void*pInB,int(*xOutput)(void*pOut,constvoid*pData,intnData),void*pOut);intsqlite3changeset_invert_strm(int(*xInput)(void*pIn,void*pData,int*pnData),void*pIn,int(*xOutput)(void*pOut,constvoid*pData,intnData),void*pOut);intsqlite3changeset_start_strm(sqlite3_changeset_iter**pp,int(*xInput)(void*pIn,void*pData,int*pnData),void*pIn);intsqlite3session_changeset_strm(sqlite3_session*pSession,int(*xOutput)(void*pOut,constvoid*pData,intnData),void*pOut);intsqlite3session_patchset_strm(sqlite3_session*pSession,int(*xOutput)(void*pOut,constvoid*pData,intnData),void*pOut);intsqlite3changegroup_add_strm(sqlite3_changegroup*,int(*xInput)(void*pIn,void*pData,int*pnData),void*pIn);intsqlite3changegroup_output_strm(sqlite3_changegroup*,int(*xOutput)(void*pOut,constvoid*pData,intnData),void*pOut);/*** Make sure we can call this stuff from C++.*/#ifdef __cplusplus}#endif#endif /* !defined(__SQLITESESSION_H_) && defined(SQLITE_ENABLE_SESSION) *//******** End of sqlite3session.h *********//******** Begin file fts5.h *********//*** 2014 May 31**** The author disclaims copyright to this source code. In place of** a legal notice, here is a blessing:**** May you do good and not evil.** May you find forgiveness for yourself and forgive others.** May you share freely, never taking more than you give.************************************************************************************ Interfaces to extend FTS5. Using the interfaces defined in this file, ** FTS5 may be extended with:**** * custom tokenizers, and** * custom auxiliary functions.*/#ifndef _FTS5_H#define _FTS5_H#ifdef __cplusplusextern"C"{#endif/*************************************************************************** CUSTOM AUXILIARY FUNCTIONS**** Virtual table implementations may overload SQL functions by implementing** the sqlite3_module.xFindFunction() method.*/typedefstructFts5ExtensionApiFts5ExtensionApi;typedefstructFts5ContextFts5Context;typedefstructFts5PhraseIterFts5PhraseIter;typedefvoid(*fts5_extension_function)(constFts5ExtensionApi*pApi,/* API offered by current FTS version */Fts5Context*pFts,/* First arg to pass to pApi functions */sqlite3_context*pCtx,/* Context for returning result/error */intnVal,/* Number of values in apVal[] array */sqlite3_value**apVal/* Array of trailing arguments */);structFts5PhraseIter{constunsignedchar*a;constunsignedchar*b;};/*** EXTENSION API FUNCTIONS**** xUserData(pFts):** Return a copy of the context pointer the extension function was ** registered with.**** xColumnTotalSize(pFts, iCol, pnToken):** If parameter iCol is less than zero, set output variable *pnToken** to the total number of tokens in the FTS5 table. Or, if iCol is** non-negative but less than the number of columns in the table, return** the total number of tokens in column iCol, considering all rows in ** the FTS5 table.**** If parameter iCol is greater than or equal to the number of columns** in the table, SQLITE_RANGE is returned. Or, if an error occurs (e.g.** an OOM condition or IO error), an appropriate SQLite error code is ** returned.**** xColumnCount(pFts):** Return the number of columns in the table.**** xColumnSize(pFts, iCol, pnToken):** If parameter iCol is less than zero, set output variable *pnToken** to the total number of tokens in the current row. Or, if iCol is** non-negative but less than the number of columns in the table, set** *pnToken to the number of tokens in column iCol of the current row.**** If parameter iCol is greater than or equal to the number of columns** in the table, SQLITE_RANGE is returned. Or, if an error occurs (e.g.** an OOM condition or IO error), an appropriate SQLite error code is ** returned.**** This function may be quite inefficient if used with an FTS5 table** created with the "columnsize=0" option.**** xColumnText:** This function attempts to retrieve the text of column iCol of the** current document. If successful, (*pz) is set to point to a buffer** containing the text in utf-8 encoding, (*pn) is set to the size in bytes** (not characters) of the buffer and SQLITE_OK is returned. Otherwise,** if an error occurs, an SQLite error code is returned and the final values** of (*pz) and (*pn) are undefined.**** xPhraseCount:** Returns the number of phrases in the current query expression.**** xPhraseSize:** Returns the number of tokens in phrase iPhrase of the query. Phrases** are numbered starting from zero.**** xInstCount:** Set *pnInst to the total number of occurrences of all phrases within** the query within the current row. Return SQLITE_OK if successful, or** an error code (i.e. SQLITE_NOMEM) if an error occurs.**** This API can be quite slow if used with an FTS5 table created with the** "detail=none" or "detail=column" option. If the FTS5 table is created ** with either "detail=none" or "detail=column" and "content=" option ** (i.e. if it is a contentless table), then this API always returns 0.**** xInst:** Query for the details of phrase match iIdx within the current row.** Phrase matches are numbered starting from zero, so the iIdx argument** should be greater than or equal to zero and smaller than the value** output by xInstCount().**** Usually, output parameter *piPhrase is set to the phrase number, *piCol** to the column in which it occurs and *piOff the token offset of the** first token of the phrase. The exception is if the table was created** with the offsets=0 option specified. In this case *piOff is always** set to -1.**** Returns SQLITE_OK if successful, or an error code (i.e. SQLITE_NOMEM) ** if an error occurs.**** This API can be quite slow if used with an FTS5 table created with the** "detail=none" or "detail=column" option. **** xRowid:** Returns the rowid of the current row.**** xTokenize:** Tokenize text using the tokenizer belonging to the FTS5 table.**** xQueryPhrase(pFts5, iPhrase, pUserData, xCallback):** This API function is used to query the FTS table for phrase iPhrase** of the current query. Specifically, a query equivalent to:**** ... FROM ftstable WHERE ftstable MATCH $p ORDER BY rowid**** with $p set to a phrase equivalent to the phrase iPhrase of the** current query is executed. Any column filter that applies to** phrase iPhrase of the current query is included in $p. For each ** row visited, the callback function passed as the fourth argument ** is invoked. The context and API objects passed to the callback ** function may be used to access the properties of each matched row.** Invoking Api.xUserData() returns a copy of the pointer passed as ** the third argument to pUserData.**** If the callback function returns any value other than SQLITE_OK, the** query is abandoned and the xQueryPhrase function returns immediately.** If the returned value is SQLITE_DONE, xQueryPhrase returns SQLITE_OK.** Otherwise, the error code is propagated upwards.**** If the query runs to completion without incident, SQLITE_OK is returned.** Or, if some error occurs before the query completes or is aborted by** the callback, an SQLite error code is returned.****** xSetAuxdata(pFts5, pAux, xDelete)**** Save the pointer passed as the second argument as the extension functions ** "auxiliary data". The pointer may then be retrieved by the current or any** future invocation of the same fts5 extension function made as part of** of the same MATCH query using the xGetAuxdata() API.**** Each extension function is allocated a single auxiliary data slot for** each FTS query (MATCH expression). If the extension function is invoked ** more than once for a single FTS query, then all invocations share a ** single auxiliary data context.**** If there is already an auxiliary data pointer when this function is** invoked, then it is replaced by the new pointer. If an xDelete callback** was specified along with the original pointer, it is invoked at this** point.**** The xDelete callback, if one is specified, is also invoked on the** auxiliary data pointer after the FTS5 query has finished.**** If an error (e.g. an OOM condition) occurs within this function, an** the auxiliary data is set to NULL and an error code returned. If the** xDelete parameter was not NULL, it is invoked on the auxiliary data** pointer before returning.****** xGetAuxdata(pFts5, bClear)**** Returns the current auxiliary data pointer for the fts5 extension ** function. See the xSetAuxdata() method for details.**** If the bClear argument is non-zero, then the auxiliary data is cleared** (set to NULL) before this function returns. In this case the xDelete,** if any, is not invoked.****** xRowCount(pFts5, pnRow)**** This function is used to retrieve the total number of rows in the table.** In other words, the same value that would be returned by:**** SELECT count(*) FROM ftstable;**** xPhraseFirst()** This function is used, along with type Fts5PhraseIter and the xPhraseNext** method, to iterate through all instances of a single query phrase within** the current row. This is the same information as is accessible via the** xInstCount/xInst APIs. While the xInstCount/xInst APIs are more convenient** to use, this API may be faster under some circumstances. To iterate ** through instances of phrase iPhrase, use the following code:**** Fts5PhraseIter iter;** int iCol, iOff;** for(pApi->xPhraseFirst(pFts, iPhrase, &iter, &iCol, &iOff);** iCol>=0;** pApi->xPhraseNext(pFts, &iter, &iCol, &iOff)** ){** // An instance of phrase iPhrase at offset iOff of column iCol** }**** The Fts5PhraseIter structure is defined above. Applications should not** modify this structure directly - it should only be used as shown above** with the xPhraseFirst() and xPhraseNext() API methods (and by** xPhraseFirstColumn() and xPhraseNextColumn() as illustrated below).**** This API can be quite slow if used with an FTS5 table created with the** "detail=none" or "detail=column" option. If the FTS5 table is created ** with either "detail=none" or "detail=column" and "content=" option ** (i.e. if it is a contentless table), then this API always iterates** through an empty set (all calls to xPhraseFirst() set iCol to -1).**** xPhraseNext()** See xPhraseFirst above.**** xPhraseFirstColumn()** This function and xPhraseNextColumn() are similar to the xPhraseFirst()** and xPhraseNext() APIs described above. The difference is that instead** of iterating through all instances of a phrase in the current row, these** APIs are used to iterate through the set of columns in the current row** that contain one or more instances of a specified phrase. For example:**** Fts5PhraseIter iter;** int iCol;** for(pApi->xPhraseFirstColumn(pFts, iPhrase, &iter, &iCol);** iCol>=0;** pApi->xPhraseNextColumn(pFts, &iter, &iCol)** ){** // Column iCol contains at least one instance of phrase iPhrase** }**** This API can be quite slow if used with an FTS5 table created with the** "detail=none" option. If the FTS5 table is created with either ** "detail=none" "content=" option (i.e. if it is a contentless table), ** then this API always iterates through an empty set (all calls to ** xPhraseFirstColumn() set iCol to -1).**** The information accessed using this API and its companion** xPhraseFirstColumn() may also be obtained using xPhraseFirst/xPhraseNext** (or xInst/xInstCount). The chief advantage of this API is that it is** significantly more efficient than those alternatives when used with** "detail=column" tables. **** xPhraseNextColumn()** See xPhraseFirstColumn above.*/structFts5ExtensionApi{intiVersion;/* Currently always set to 3 */void*(*xUserData)(Fts5Context*);int(*xColumnCount)(Fts5Context*);int(*xRowCount)(Fts5Context*,sqlite3_int64*pnRow);int(*xColumnTotalSize)(Fts5Context*,intiCol,sqlite3_int64*pnToken);int(*xTokenize)(Fts5Context*,constchar*pText,intnText,/* Text to tokenize */void*pCtx,/* Context passed to xToken() */int(*xToken)(void*,int,constchar*,int,int,int)/* Callback */);int(*xPhraseCount)(Fts5Context*);int(*xPhraseSize)(Fts5Context*,intiPhrase);int(*xInstCount)(Fts5Context*,int*pnInst);int(*xInst)(Fts5Context*,intiIdx,int*piPhrase,int*piCol,int*piOff);sqlite3_int64(*xRowid)(Fts5Context*);int(*xColumnText)(Fts5Context*,intiCol,constchar**pz,int*pn);int(*xColumnSize)(Fts5Context*,intiCol,int*pnToken);int(*xQueryPhrase)(Fts5Context*,intiPhrase,void*pUserData,int(*)(constFts5ExtensionApi*,Fts5Context*,void*));int(*xSetAuxdata)(Fts5Context*,void*pAux,void(*xDelete)(void*));void*(*xGetAuxdata)(Fts5Context*,intbClear);int(*xPhraseFirst)(Fts5Context*,intiPhrase,Fts5PhraseIter*,int*,int*);void(*xPhraseNext)(Fts5Context*,Fts5PhraseIter*,int*piCol,int*piOff);int(*xPhraseFirstColumn)(Fts5Context*,intiPhrase,Fts5PhraseIter*,int*);void(*xPhraseNextColumn)(Fts5Context*,Fts5PhraseIter*,int*piCol);};/* ** CUSTOM AUXILIARY FUNCTIONS*************************************************************************//*************************************************************************** CUSTOM TOKENIZERS**** Applications may also register custom tokenizer types. A tokenizer ** is registered by providing fts5 with a populated instance of the ** following structure. All structure methods must be defined, setting** any member of the fts5_tokenizer struct to NULL leads to undefined** behaviour. The structure methods are expected to function as follows:**** xCreate:** This function is used to allocate and initialize a tokenizer instance.** A tokenizer instance is required to actually tokenize text.**** The first argument passed to this function is a copy of the (void*)** pointer provided by the application when the fts5_tokenizer object** was registered with FTS5 (the third argument to xCreateTokenizer()). ** The second and third arguments are an array of nul-terminated strings** containing the tokenizer arguments, if any, specified following the** tokenizer name as part of the CREATE VIRTUAL TABLE statement used** to create the FTS5 table.**** The final argument is an output variable. If successful, (*ppOut) ** should be set to point to the new tokenizer handle and SQLITE_OK** returned. If an error occurs, some value other than SQLITE_OK should** be returned. In this case, fts5 assumes that the final value of *ppOut ** is undefined.**** xDelete:** This function is invoked to delete a tokenizer handle previously** allocated using xCreate(). Fts5 guarantees that this function will** be invoked exactly once for each successful call to xCreate().**** xTokenize:** This function is expected to tokenize the nText byte string indicated ** by argument pText. pText may or may not be nul-terminated. The first** argument passed to this function is a pointer to an Fts5Tokenizer object** returned by an earlier call to xCreate().**** The second argument indicates the reason that FTS5 is requesting** tokenization of the supplied text. This is always one of the following** four values:**** <ul><li> <b>FTS5_TOKENIZE_DOCUMENT</b> - A document is being inserted into** or removed from the FTS table. The tokenizer is being invoked to** determine the set of tokens to add to (or delete from) the** FTS index.**** <li> <b>FTS5_TOKENIZE_QUERY</b> - A MATCH query is being executed ** against the FTS index. The tokenizer is being called to tokenize ** a bareword or quoted string specified as part of the query.**** <li> <b>(FTS5_TOKENIZE_QUERY | FTS5_TOKENIZE_PREFIX)</b> - Same as** FTS5_TOKENIZE_QUERY, except that the bareword or quoted string is** followed by a "*" character, indicating that the last token** returned by the tokenizer will be treated as a token prefix.**** <li> <b>FTS5_TOKENIZE_AUX</b> - The tokenizer is being invoked to ** satisfy an fts5_api.xTokenize() request made by an auxiliary** function. Or an fts5_api.xColumnSize() request made by the same** on a columnsize=0 database. ** </ul>**** For each token in the input string, the supplied callback xToken() must** be invoked. The first argument to it should be a copy of the pointer** passed as the second argument to xTokenize(). The third and fourth** arguments are a pointer to a buffer containing the token text, and the** size of the token in bytes. The 4th and 5th arguments are the byte offsets** of the first byte of and first byte immediately following the text from** which the token is derived within the input.**** The second argument passed to the xToken() callback ("tflags") should** normally be set to 0. The exception is if the tokenizer supports ** synonyms. In this case see the discussion below for details.**** FTS5 assumes the xToken() callback is invoked for each token in the ** order that they occur within the input text.**** If an xToken() callback returns any value other than SQLITE_OK, then** the tokenization should be abandoned and the xTokenize() method should** immediately return a copy of the xToken() return value. Or, if the** input buffer is exhausted, xTokenize() should return SQLITE_OK. Finally,** if an error occurs with the xTokenize() implementation itself, it** may abandon the tokenization and return any error code other than** SQLITE_OK or SQLITE_DONE.**** SYNONYM SUPPORT**** Custom tokenizers may also support synonyms. Consider a case in which a** user wishes to query for a phrase such as "first place". Using the ** built-in tokenizers, the FTS5 query 'first + place' will match instances** of "first place" within the document set, but not alternative forms** such as "1st place". In some applications, it would be better to match** all instances of "first place" or "1st place" regardless of which form** the user specified in the MATCH query text.**** There are several ways to approach this in FTS5:**** <ol><li> By mapping all synonyms to a single token. In this case, the ** In the above example, this means that the tokenizer returns the** same token for inputs "first" and "1st". Say that token is in** fact "first", so that when the user inserts the document "I won** 1st place" entries are added to the index for tokens "i", "won",** "first" and "place". If the user then queries for '1st + place',** the tokenizer substitutes "first" for "1st" and the query works** as expected.**** <li> By adding multiple synonyms for a single term to the FTS index.** In this case, when tokenizing query text, the tokenizer may ** provide multiple synonyms for a single term within the document.** FTS5 then queries the index for each synonym individually. For** example, faced with the query:**** <codeblock>** ... MATCH 'first place'</codeblock>**** the tokenizer offers both "1st" and "first" as synonyms for the** first token in the MATCH query and FTS5 effectively runs a query ** similar to:**** <codeblock>** ... MATCH '(first OR 1st) place'</codeblock>**** except that, for the purposes of auxiliary functions, the query** still appears to contain just two phrases - "(first OR 1st)" ** being treated as a single phrase.**** <li> By adding multiple synonyms for a single term to the FTS index.** Using this method, when tokenizing document text, the tokenizer** provides multiple synonyms for each token. So that when a ** document such as "I won first place" is tokenized, entries are** added to the FTS index for "i", "won", "first", "1st" and** "place".**** This way, even if the tokenizer does not provide synonyms** when tokenizing query text (it should not - to do would be** inefficient), it doesn't matter if the user queries for ** 'first + place' or '1st + place', as there are entires in the** FTS index corresponding to both forms of the first token.** </ol>**** Whether it is parsing document or query text, any call to xToken that** specifies a <i>tflags</i> argument with the FTS5_TOKEN_COLOCATED bit** is considered to supply a synonym for the previous token. For example,** when parsing the document "I won first place", a tokenizer that supports** synonyms would call xToken() 5 times, as follows:**** <codeblock>** xToken(pCtx, 0, "i", 1, 0, 1);** xToken(pCtx, 0, "won", 3, 2, 5);** xToken(pCtx, 0, "first", 5, 6, 11);** xToken(pCtx, FTS5_TOKEN_COLOCATED, "1st", 3, 6, 11);** xToken(pCtx, 0, "place", 5, 12, 17);**</codeblock>**** It is an error to specify the FTS5_TOKEN_COLOCATED flag the first time** xToken() is called. Multiple synonyms may be specified for a single token** by making multiple calls to xToken(FTS5_TOKEN_COLOCATED) in sequence. ** There is no limit to the number of synonyms that may be provided for a** single token.**** In many cases, method (1) above is the best approach. It does not add ** extra data to the FTS index or require FTS5 to query for multiple terms,** so it is efficient in terms of disk space and query speed. However, it** does not support prefix queries very well. If, as suggested above, the** token "first" is subsituted for "1st" by the tokenizer, then the query:**** <codeblock>** ... MATCH '1s*'</codeblock>**** will not match documents that contain the token "1st" (as the tokenizer** will probably not map "1s" to any prefix of "first").**** For full prefix support, method (3) may be preferred. In this case, ** because the index contains entries for both "first" and "1st", prefix** queries such as 'fi*' or '1s*' will match correctly. However, because** extra entries are added to the FTS index, this method uses more space** within the database.**** Method (2) offers a midpoint between (1) and (3). Using this method,** a query such as '1s*' will match documents that contain the literal ** token "1st", but not "first" (assuming the tokenizer is not able to** provide synonyms for prefixes). However, a non-prefix query like '1st'** will match against "1st" and "first". This method does not require** extra disk space, as no extra entries are added to the FTS index. ** On the other hand, it may require more CPU cycles to run MATCH queries,** as separate queries of the FTS index are required for each synonym.**** When using methods (2) or (3), it is important that the tokenizer only** provide synonyms when tokenizing document text (method (2)) or query** text (method (3)), not both. Doing so will not cause any errors, but is** inefficient.*/typedefstructFts5TokenizerFts5Tokenizer;typedefstructfts5_tokenizerfts5_tokenizer;structfts5_tokenizer{int(*xCreate)(void*,constchar**azArg,intnArg,Fts5Tokenizer**ppOut);void(*xDelete)(Fts5Tokenizer*);int(*xTokenize)(Fts5Tokenizer*,void*pCtx,intflags,/* Mask of FTS5_TOKENIZE_* flags */constchar*pText,intnText,int(*xToken)(void*pCtx,/* Copy of 2nd argument to xTokenize() */inttflags,/* Mask of FTS5_TOKEN_* flags */constchar*pToken,/* Pointer to buffer containing token */intnToken,/* Size of token in bytes */intiStart,/* Byte offset of token within input text */intiEnd/* Byte offset of end of token within input text */));};/* Flags that may be passed as the third argument to xTokenize() */#define FTS5_TOKENIZE_QUERY 0x0001#define FTS5_TOKENIZE_PREFIX 0x0002#define FTS5_TOKENIZE_DOCUMENT 0x0004#define FTS5_TOKENIZE_AUX 0x0008/* Flags that may be passed by the tokenizer implementation back to FTS5** as the third argument to the supplied xToken callback. */#define FTS5_TOKEN_COLOCATED 0x0001 /* Same position as prev. token *//*** END OF CUSTOM TOKENIZERS*************************************************************************//*************************************************************************** FTS5 EXTENSION REGISTRATION API*/typedefstructfts5_apifts5_api;structfts5_api{intiVersion;/* Currently always set to 2 *//* Create a new tokenizer */int(*xCreateTokenizer)(fts5_api*pApi,constchar*zName,void*pContext,fts5_tokenizer*pTokenizer,void(*xDestroy)(void*));/* Find an existing tokenizer */int(*xFindTokenizer)(fts5_api*pApi,constchar*zName,void**ppContext,fts5_tokenizer*pTokenizer);/* Create a new auxiliary function */int(*xCreateFunction)(fts5_api*pApi,constchar*zName,void*pContext,fts5_extension_functionxFunction,void(*xDestroy)(void*));};/*** END OF REGISTRATION API*************************************************************************/#ifdef __cplusplus}/* end of the 'extern "C"' block */#endif#endif /* _FTS5_H *//******** End of fts5.h *********/