# Importing sqlite3.h # Generated at 2021-01-10T20:51:10+02:00 # Command line: # /home/yglukhov/.nimble/pkgs/nimterop-0.4.4/nimterop/toast --preprocess --pnim --symOverride=sqlite3_vmprintf,sqlite3_vsnprintf,sqlite3_str_vappendf,sqlite_int64,sqlite_uint64,sqlite3_int64,sqlite3_uint64 --nim:/home/yglukhov/Projects/nim-new/bin/nim --pluginSourcePath=/home/yglukhov/.cache/nim/nimterop/cPlugins/nimterop_93481909.nim sqlite3.h {.hint[ConvFromXtoItselfNotNeeded]: off.} const headersqlite3 {.used.} = "sqlite3.h" # # ** 2001-09-15 # ** # ** 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. # # # ** Make sure we can call this stuff from C++. # # # ** Provide the ability to override linkage features of the interface. # # # ** 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. # # # ** Ensure these symbols were not defined by some previous header file. # # # ** 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 # ** Fossil configuration management # ** system. ^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 a SHA1 # ** or SHA3-256 hash of the entire source tree. If the source code has # ** been edited in any way since it was last checked in, then the last # ** four hexadecimal digits of the hash may be modified. # ** # ** See also: [sqlite3_libversion()], # ** [sqlite3_libversion_number()], [sqlite3_sourceid()], # ** [sqlite_version()] and [sqlite_source_id()]. # SQLITE_VERSION* = "3.34.0" SQLITE_VERSION_NUMBER* = 3034000 SQLITE_SOURCE_ID* = "2020-12-01 16:14:00 a26b6597e3ae272231b96f9982c3bcc17ddec2f2b6eb4df06a224b91089fed5b" # # ** 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] # SQLITE_OK* = 0 # beginning-of-error-codes SQLITE_ERROR* = 1 SQLITE_INTERNAL* = 2 SQLITE_PERM* = 3 SQLITE_ABORT* = 4 SQLITE_BUSY* = 5 SQLITE_LOCKED* = 6 SQLITE_NOMEM* = 7 SQLITE_READONLY* = 8 SQLITE_INTERRUPT* = 9 SQLITE_IOERR* = 10 SQLITE_CORRUPT* = 11 SQLITE_NOTFOUND* = 12 SQLITE_FULL* = 13 SQLITE_CANTOPEN* = 14 SQLITE_PROTOCOL* = 15 SQLITE_EMPTY* = 16 SQLITE_SCHEMA* = 17 SQLITE_TOOBIG* = 18 SQLITE_CONSTRAINT* = 19 SQLITE_MISMATCH* = 20 SQLITE_MISUSE* = 21 SQLITE_NOLFS* = 22 SQLITE_AUTH* = 23 SQLITE_FORMAT* = 24 SQLITE_RANGE* = 25 SQLITE_NOTADB* = 26 SQLITE_NOTICE* = 27 SQLITE_WARNING* = 28 SQLITE_ROW* = 100 SQLITE_DONE* = 101 # 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()]. # # # ** 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. # SQLITE_OPEN_READONLY* = 0x00000001 SQLITE_OPEN_READWRITE* = 0x00000002 SQLITE_OPEN_CREATE* = 0x00000004 SQLITE_OPEN_DELETEONCLOSE* = 0x00000008 SQLITE_OPEN_EXCLUSIVE* = 0x00000010 SQLITE_OPEN_AUTOPROXY* = 0x00000020 SQLITE_OPEN_URI* = 0x00000040 SQLITE_OPEN_MEMORY* = 0x00000080 SQLITE_OPEN_MAIN_DB* = 0x00000100 SQLITE_OPEN_TEMP_DB* = 0x00000200 SQLITE_OPEN_TRANSIENT_DB* = 0x00000400 SQLITE_OPEN_MAIN_JOURNAL* = 0x00000800 SQLITE_OPEN_TEMP_JOURNAL* = 0x00001000 SQLITE_OPEN_SUBJOURNAL* = 0x00002000 SQLITE_OPEN_SUPER_JOURNAL* = 0x00004000 SQLITE_OPEN_NOMUTEX* = 0x00008000 SQLITE_OPEN_FULLMUTEX* = 0x00010000 SQLITE_OPEN_SHAREDCACHE* = 0x00020000 SQLITE_OPEN_PRIVATECACHE* = 0x00040000 SQLITE_OPEN_WAL* = 0x00080000 SQLITE_OPEN_NOFOLLOW* = 0x01000000 # Reserved: 0x00F00000 # Legacy compatibility: SQLITE_OPEN_MASTER_JOURNAL* = 0x00004000 # # ** 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 indicates 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. # ** # ** The SQLITE_IOCAP_BATCH_ATOMIC property means that the underlying # ** filesystem supports doing multiple write operations atomically when those # ** write operations are bracketed by [SQLITE_FCNTL_BEGIN_ATOMIC_WRITE] and # ** [SQLITE_FCNTL_COMMIT_ATOMIC_WRITE]. # SQLITE_IOCAP_ATOMIC* = 0x00000001 SQLITE_IOCAP_ATOMIC512* = 0x00000002 SQLITE_IOCAP_ATOMIC1K* = 0x00000004 SQLITE_IOCAP_ATOMIC2K* = 0x00000008 SQLITE_IOCAP_ATOMIC4K* = 0x00000010 SQLITE_IOCAP_ATOMIC8K* = 0x00000020 SQLITE_IOCAP_ATOMIC16K* = 0x00000040 SQLITE_IOCAP_ATOMIC32K* = 0x00000080 SQLITE_IOCAP_ATOMIC64K* = 0x00000100 SQLITE_IOCAP_SAFE_APPEND* = 0x00000200 SQLITE_IOCAP_SEQUENTIAL* = 0x00000400 SQLITE_IOCAP_UNDELETABLE_WHEN_OPEN* = 0x00000800 SQLITE_IOCAP_POWERSAFE_OVERWRITE* = 0x00001000 SQLITE_IOCAP_IMMUTABLE* = 0x00002000 SQLITE_IOCAP_BATCH_ATOMIC* = 0x00004000 # # ** 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. # SQLITE_LOCK_NONE* = 0 SQLITE_LOCK_SHARED* = 1 SQLITE_LOCK_RESERVED* = 2 SQLITE_LOCK_PENDING* = 3 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.) # SQLITE_SYNC_NORMAL* = 0x00002 SQLITE_SYNC_FULL* = 0x00003 SQLITE_SYNC_DATAONLY* = 0x00010 # # ** 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. # ** # ** # SQLITE_FCNTL_LOCKSTATE* = 1 SQLITE_FCNTL_GET_LOCKPROXYFILE* = 2 SQLITE_FCNTL_SET_LOCKPROXYFILE* = 3 SQLITE_FCNTL_LAST_ERRNO* = 4 SQLITE_FCNTL_SIZE_HINT* = 5 SQLITE_FCNTL_CHUNK_SIZE* = 6 SQLITE_FCNTL_FILE_POINTER* = 7 SQLITE_FCNTL_SYNC_OMITTED* = 8 SQLITE_FCNTL_WIN32_AV_RETRY* = 9 SQLITE_FCNTL_PERSIST_WAL* = 10 SQLITE_FCNTL_OVERWRITE* = 11 SQLITE_FCNTL_VFSNAME* = 12 SQLITE_FCNTL_POWERSAFE_OVERWRITE* = 13 SQLITE_FCNTL_PRAGMA* = 14 SQLITE_FCNTL_BUSYHANDLER* = 15 SQLITE_FCNTL_TEMPFILENAME* = 16 SQLITE_FCNTL_MMAP_SIZE* = 18 SQLITE_FCNTL_TRACE* = 19 SQLITE_FCNTL_HAS_MOVED* = 20 SQLITE_FCNTL_SYNC* = 21 SQLITE_FCNTL_COMMIT_PHASETWO* = 22 SQLITE_FCNTL_WIN32_SET_HANDLE* = 23 SQLITE_FCNTL_WAL_BLOCK* = 24 SQLITE_FCNTL_ZIPVFS* = 25 SQLITE_FCNTL_RBU* = 26 SQLITE_FCNTL_VFS_POINTER* = 27 SQLITE_FCNTL_JOURNAL_POINTER* = 28 SQLITE_FCNTL_WIN32_GET_HANDLE* = 29 SQLITE_FCNTL_PDB* = 30 SQLITE_FCNTL_BEGIN_ATOMIC_WRITE* = 31 SQLITE_FCNTL_COMMIT_ATOMIC_WRITE* = 32 SQLITE_FCNTL_ROLLBACK_ATOMIC_WRITE* = 33 SQLITE_FCNTL_LOCK_TIMEOUT* = 34 SQLITE_FCNTL_DATA_VERSION* = 35 SQLITE_FCNTL_SIZE_LIMIT* = 36 SQLITE_FCNTL_CKPT_DONE* = 37 SQLITE_FCNTL_RESERVE_BYTES* = 38 SQLITE_FCNTL_CKPT_START* = 39 # # ** 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. # SQLITE_ACCESS_EXISTS* = 0 SQLITE_ACCESS_READWRITE* = 1 SQLITE_ACCESS_READ* = 2 # # ** 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: # ** # ** # ** # ** 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. # SQLITE_SHM_UNLOCK* = 1 SQLITE_SHM_LOCK* = 2 SQLITE_SHM_SHARED* = 4 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 # SQLITE_SHM_NLOCK* = 8 # # ** 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. # ** # **
# ** [[SQLITE_CONFIG_SINGLETHREAD]]
SQLITE_CONFIG_SINGLETHREAD
# **
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.
# ** # ** [[SQLITE_CONFIG_MULTITHREAD]]
SQLITE_CONFIG_MULTITHREAD
# **
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.
# ** # ** [[SQLITE_CONFIG_SERIALIZED]]
SQLITE_CONFIG_SERIALIZED
# **
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.
# ** # ** [[SQLITE_CONFIG_MALLOC]]
SQLITE_CONFIG_MALLOC
# **
^(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.
# ** # ** [[SQLITE_CONFIG_GETMALLOC]]
SQLITE_CONFIG_GETMALLOC
# **
^(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.
# ** # ** [[SQLITE_CONFIG_SMALL_MALLOC]]
SQLITE_CONFIG_SMALL_MALLOC
# **
^The SQLITE_CONFIG_SMALL_MALLOC option takes single argument of # ** type int, interpreted as a boolean, which if true provides a hint to # ** SQLite that it should avoid large memory allocations if possible. # ** SQLite will run faster if it is free to make large memory allocations, # ** but some application might prefer to run slower in exchange for # ** guarantees about memory fragmentation that are possible if large # ** allocations are avoided. This hint is normally off. # **
# ** # ** [[SQLITE_CONFIG_MEMSTATUS]]
SQLITE_CONFIG_MEMSTATUS
# **
^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: # ** )^ # ** ^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. # **
# ** # ** [[SQLITE_CONFIG_SCRATCH]]
SQLITE_CONFIG_SCRATCH
# **
The SQLITE_CONFIG_SCRATCH option is no longer used. # **
# ** # ** [[SQLITE_CONFIG_PAGECACHE]]
SQLITE_CONFIG_PAGECACHE
# **
^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-defined 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.
# ** # ** [[SQLITE_CONFIG_HEAP]]
SQLITE_CONFIG_HEAP
# **
^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_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.
# ** # ** [[SQLITE_CONFIG_MUTEX]]
SQLITE_CONFIG_MUTEX
# **
^(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].
# ** # ** [[SQLITE_CONFIG_GETMUTEX]]
SQLITE_CONFIG_GETMUTEX
# **
^(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].
# ** # ** [[SQLITE_CONFIG_LOOKASIDE]]
SQLITE_CONFIG_LOOKASIDE
# **
^(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 default lookaside size. The [SQLITE_DBCONFIG_LOOKASIDE] # ** option to [sqlite3_db_config()] can be used to change the lookaside # ** configuration on individual connections.)^
# ** # ** [[SQLITE_CONFIG_PCACHE2]]
SQLITE_CONFIG_PCACHE2
# **
^(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.
# ** # ** [[SQLITE_CONFIG_GETPCACHE2]]
SQLITE_CONFIG_GETPCACHE2
# **
^(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.)^
# ** # ** [[SQLITE_CONFIG_LOG]]
SQLITE_CONFIG_LOG
# **
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.
# ** # ** [[SQLITE_CONFIG_URI]]
SQLITE_CONFIG_URI # **
^(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]]
SQLITE_CONFIG_COVERING_INDEX_SCAN # **
^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]] # **
SQLITE_CONFIG_PCACHE and SQLITE_CONFIG_GETPCACHE # **
These options are obsolete and should not be used by new code. # ** They are retained for backwards compatibility but are now no-ops. # **
# ** # ** [[SQLITE_CONFIG_SQLLOG]] # **
SQLITE_CONFIG_SQLLOG # **
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.
# ** # ** [[SQLITE_CONFIG_MMAP_SIZE]] # **
SQLITE_CONFIG_MMAP_SIZE # **
^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]] # **
SQLITE_CONFIG_WIN32_HEAPSIZE # **
^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]] # **
SQLITE_CONFIG_PCACHE_HDRSZ # **
^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]] # **
SQLITE_CONFIG_PMASZ # **
^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]] # **
SQLITE_CONFIG_STMTJRNL_SPILL # **
^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. # ** # ** [[SQLITE_CONFIG_SORTERREF_SIZE]] # **
SQLITE_CONFIG_SORTERREF_SIZE # **
The SQLITE_CONFIG_SORTERREF_SIZE option accepts a single parameter # ** of type (int) - the new value of the sorter-reference size threshold. # ** Usually, when SQLite uses an external sort to order records according # ** to an ORDER BY clause, all fields required by the caller are present in the # ** sorted records. However, if SQLite determines based on the declared type # ** of a table column that its values are likely to be very large - larger # ** than the configured sorter-reference size threshold - then a reference # ** is stored in each sorted record and the required column values loaded # ** from the database as records are returned in sorted order. The default # ** value for this option is to never use this optimization. Specifying a # ** negative value for this option restores the default behaviour. # ** This option is only available if SQLite is compiled with the # ** [SQLITE_ENABLE_SORTER_REFERENCES] compile-time option. # ** # ** [[SQLITE_CONFIG_MEMDB_MAXSIZE]] # **
SQLITE_CONFIG_MEMDB_MAXSIZE # **
The SQLITE_CONFIG_MEMDB_MAXSIZE option accepts a single parameter # ** [sqlite3_int64] parameter which is the default maximum size for an in-memory # ** database created using [sqlite3_deserialize()]. This default maximum # ** size can be adjusted up or down for individual databases using the # ** [SQLITE_FCNTL_SIZE_LIMIT] [sqlite3_file_control|file-control]. If this # ** configuration setting is never used, then the default maximum is determined # ** by the [SQLITE_MEMDB_DEFAULT_MAXSIZE] compile-time option. If that # ** compile-time option is not set, then the default maximum is 1073741824. # **
# SQLITE_CONFIG_SINGLETHREAD* = 1 SQLITE_CONFIG_MULTITHREAD* = 2 SQLITE_CONFIG_SERIALIZED* = 3 SQLITE_CONFIG_MALLOC* = 4 SQLITE_CONFIG_GETMALLOC* = 5 SQLITE_CONFIG_SCRATCH* = 6 SQLITE_CONFIG_PAGECACHE* = 7 SQLITE_CONFIG_HEAP* = 8 SQLITE_CONFIG_MEMSTATUS* = 9 SQLITE_CONFIG_MUTEX* = 10 SQLITE_CONFIG_GETMUTEX* = 11 # previously SQLITE_CONFIG_CHUNKALLOC 12 which is now unused. SQLITE_CONFIG_LOOKASIDE* = 13 SQLITE_CONFIG_PCACHE* = 14 SQLITE_CONFIG_GETPCACHE* = 15 SQLITE_CONFIG_LOG* = 16 SQLITE_CONFIG_URI* = 17 SQLITE_CONFIG_PCACHE2* = 18 SQLITE_CONFIG_GETPCACHE2* = 19 SQLITE_CONFIG_COVERING_INDEX_SCAN* = 20 SQLITE_CONFIG_SQLLOG* = 21 SQLITE_CONFIG_MMAP_SIZE* = 22 SQLITE_CONFIG_WIN32_HEAPSIZE* = 23 SQLITE_CONFIG_PCACHE_HDRSZ* = 24 SQLITE_CONFIG_PMASZ* = 25 SQLITE_CONFIG_STMTJRNL_SPILL* = 26 SQLITE_CONFIG_SMALL_MALLOC* = 27 SQLITE_CONFIG_SORTERREF_SIZE* = 28 SQLITE_CONFIG_MEMDB_MAXSIZE* = 29 # # ** 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. # ** # **
# ** [[SQLITE_DBCONFIG_LOOKASIDE]] # **
SQLITE_DBCONFIG_LOOKASIDE
# **
^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].)^
# ** # ** [[SQLITE_DBCONFIG_ENABLE_FKEY]] # **
SQLITE_DBCONFIG_ENABLE_FKEY
# **
^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.
# ** # ** [[SQLITE_DBCONFIG_ENABLE_TRIGGER]] # **
SQLITE_DBCONFIG_ENABLE_TRIGGER
# **
^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.
# ** # ** [[SQLITE_DBCONFIG_ENABLE_VIEW]] # **
SQLITE_DBCONFIG_ENABLE_VIEW
# **
^This option is used to enable or disable [CREATE VIEW | views]. # ** There should be two additional arguments. # ** The first argument is an integer which is 0 to disable views, # ** positive to enable views 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 views are disabled or enabled # ** following this call. The second parameter may be a NULL pointer, in # ** which case the view setting is not reported back.
# ** # ** [[SQLITE_DBCONFIG_ENABLE_FTS3_TOKENIZER]] # **
SQLITE_DBCONFIG_ENABLE_FTS3_TOKENIZER
# **
^This option is used to enable or disable 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.
# ** # ** [[SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION]] # **
SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION
# **
^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. # **
# ** # ** [[SQLITE_DBCONFIG_MAINDBNAME]]
SQLITE_DBCONFIG_MAINDBNAME
# **
^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. # **
# ** # ** [[SQLITE_DBCONFIG_NO_CKPT_ON_CLOSE]] # **
SQLITE_DBCONFIG_NO_CKPT_ON_CLOSE
# **
Usually, when a database in wal mode is closed or detached from a # ** database handle, SQLite checks if this will mean that there are now no # ** connections at all to the database. If so, it performs a checkpoint # ** operation before closing the connection. This option may be used to # ** override this behaviour. The first parameter passed to this operation # ** is an integer - positive to disable checkpoints-on-close, or zero (the # ** default) to enable them, and 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 checkpoints-on-close # ** have been disabled - 0 if they are not disabled, 1 if they are. # **
# ** # ** [[SQLITE_DBCONFIG_ENABLE_QPSG]]
SQLITE_DBCONFIG_ENABLE_QPSG
# **
^(The SQLITE_DBCONFIG_ENABLE_QPSG option activates or deactivates # ** the [query planner stability guarantee] (QPSG). When the QPSG is active, # ** a single SQL query statement will always use the same algorithm regardless # ** of values of [bound parameters].)^ The QPSG disables some query optimizations # ** that look at the values of bound parameters, which can make some queries # ** slower. But the QPSG has the advantage of more predictable behavior. With # ** the QPSG active, SQLite will always use the same query plan in the field as # ** was used during testing in the lab. # ** The first argument to this setting is an integer which is 0 to disable # ** the QPSG, positive to enable QPSG, 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 the QPSG is disabled or enabled # ** following this call. # **
# ** # ** [[SQLITE_DBCONFIG_TRIGGER_EQP]]
SQLITE_DBCONFIG_TRIGGER_EQP
# **
By default, the output of EXPLAIN QUERY PLAN commands does not # ** include output for any operations performed by trigger programs. This # ** option is used to set or clear (the default) a flag that governs this # ** behavior. The first parameter passed to this operation is an integer - # ** positive to enable output for trigger programs, or zero to disable it, # ** 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 output-for-triggers has been disabled - 0 if # ** it is not disabled, 1 if it is. # **
# ** # ** [[SQLITE_DBCONFIG_RESET_DATABASE]]
SQLITE_DBCONFIG_RESET_DATABASE
# **
Set the SQLITE_DBCONFIG_RESET_DATABASE flag and then run # ** [VACUUM] in order to reset a database back to an empty database # ** with no schema and no content. The following process works even for # ** a badly corrupted database file: # **
    # **
  1. If the database connection is newly opened, make sure it has read the # ** database schema by preparing then discarding some query against the # ** database, or calling sqlite3_table_column_metadata(), ignoring any # ** errors. This step is only necessary if the application desires to keep # ** the database in WAL mode after the reset if it was in WAL mode before # ** the reset. # **
  2. sqlite3_db_config(db, SQLITE_DBCONFIG_RESET_DATABASE, 1, 0); # **
  3. [sqlite3_exec](db, "[VACUUM]", 0, 0, 0); # **
  4. sqlite3_db_config(db, SQLITE_DBCONFIG_RESET_DATABASE, 0, 0); # **
# ** Because resetting a database is destructive and irreversible, the # ** process requires the use of this obscure API and multiple steps to help # ** ensure that it does not happen by accident. # ** # ** [[SQLITE_DBCONFIG_DEFENSIVE]]
SQLITE_DBCONFIG_DEFENSIVE
# **
The SQLITE_DBCONFIG_DEFENSIVE option activates or deactivates the # ** "defensive" flag for a database connection. When the defensive # ** flag is enabled, language features that allow ordinary SQL to # ** deliberately corrupt the database file are disabled. The disabled # ** features include but are not limited to the following: # ** # **
# ** # ** [[SQLITE_DBCONFIG_WRITABLE_SCHEMA]]
SQLITE_DBCONFIG_WRITABLE_SCHEMA
# **
The SQLITE_DBCONFIG_WRITABLE_SCHEMA option activates or deactivates the # ** "writable_schema" flag. This has the same effect and is logically equivalent # ** to setting [PRAGMA writable_schema=ON] or [PRAGMA writable_schema=OFF]. # ** The first argument to this setting is an integer which is 0 to disable # ** the writable_schema, positive to enable writable_schema, 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 the writable_schema # ** is enabled or disabled following this call. # **
# ** # ** [[SQLITE_DBCONFIG_LEGACY_ALTER_TABLE]] # **
SQLITE_DBCONFIG_LEGACY_ALTER_TABLE
# **
The SQLITE_DBCONFIG_LEGACY_ALTER_TABLE option activates or deactivates # ** the legacy behavior of the [ALTER TABLE RENAME] command such it # ** behaves as it did prior to [version 3.24.0] (2018-06-04). See the # ** "Compatibility Notice" on the [ALTER TABLE RENAME documentation] for # ** additional information. This feature can also be turned on and off # ** using the [PRAGMA legacy_alter_table] statement. # **
# ** # ** [[SQLITE_DBCONFIG_DQS_DML]] # **
SQLITE_DBCONFIG_DQS_DML # **
The SQLITE_DBCONFIG_DQS_DML option activates or deactivates # ** the legacy [double-quoted string literal] misfeature for DML statements # ** only, that is DELETE, INSERT, SELECT, and UPDATE statements. The # ** default value of this setting is determined by the [-DSQLITE_DQS] # ** compile-time option. # **
# ** # ** [[SQLITE_DBCONFIG_DQS_DDL]] # **
SQLITE_DBCONFIG_DQS_DDL # **
The SQLITE_DBCONFIG_DQS option activates or deactivates # ** the legacy [double-quoted string literal] misfeature for DDL statements, # ** such as CREATE TABLE and CREATE INDEX. The # ** default value of this setting is determined by the [-DSQLITE_DQS] # ** compile-time option. # **
# ** # ** [[SQLITE_DBCONFIG_TRUSTED_SCHEMA]] # **
SQLITE_DBCONFIG_TRUSTED_SCHEMA # **
The SQLITE_DBCONFIG_TRUSTED_SCHEMA option tells SQLite to # ** assume that database schemas are untainted by malicious content. # ** When the SQLITE_DBCONFIG_TRUSTED_SCHEMA option is disabled, SQLite # ** takes additional defensive steps to protect the application from harm # ** including: # ** # ** This setting defaults to "on" for legacy compatibility, however # ** all applications are advised to turn it off if possible. This setting # ** can also be controlled using the [PRAGMA trusted_schema] statement. # **
# ** # ** [[SQLITE_DBCONFIG_LEGACY_FILE_FORMAT]] # **
SQLITE_DBCONFIG_LEGACY_FILE_FORMAT # **
The SQLITE_DBCONFIG_LEGACY_FILE_FORMAT option activates or deactivates # ** the legacy file format flag. When activated, this flag causes all newly # ** created database file to have a schema format version number (the 4-byte # ** integer found at offset 44 into the database header) of 1. This in turn # ** means that the resulting database file will be readable and writable by # ** any SQLite version back to 3.0.0 ([dateof:3.0.0]). Without this setting, # ** newly created databases are generally not understandable by SQLite versions # ** prior to 3.3.0 ([dateof:3.3.0]). As these words are written, there # ** is now scarcely any need to generated database files that are compatible # ** all the way back to version 3.0.0, and so this setting is of little # ** practical use, but is provided so that SQLite can continue to claim the # ** ability to generate new database files that are compatible with version # ** 3.0.0. # **

Note that when the SQLITE_DBCONFIG_LEGACY_FILE_FORMAT setting is on, # ** the [VACUUM] command will fail with an obscure error when attempting to # ** process a table with generated columns and a descending index. This is # ** not considered a bug since SQLite versions 3.3.0 and earlier do not support # ** either generated columns or decending indexes. # **

# **
# SQLITE_DBCONFIG_MAINDBNAME* = 1000 SQLITE_DBCONFIG_LOOKASIDE* = 1001 SQLITE_DBCONFIG_ENABLE_FKEY* = 1002 SQLITE_DBCONFIG_ENABLE_TRIGGER* = 1003 SQLITE_DBCONFIG_ENABLE_FTS3_TOKENIZER* = 1004 SQLITE_DBCONFIG_ENABLE_LOAD_EXTENSION* = 1005 SQLITE_DBCONFIG_NO_CKPT_ON_CLOSE* = 1006 SQLITE_DBCONFIG_ENABLE_QPSG* = 1007 SQLITE_DBCONFIG_TRIGGER_EQP* = 1008 SQLITE_DBCONFIG_RESET_DATABASE* = 1009 SQLITE_DBCONFIG_DEFENSIVE* = 1010 SQLITE_DBCONFIG_WRITABLE_SCHEMA* = 1011 SQLITE_DBCONFIG_LEGACY_ALTER_TABLE* = 1012 SQLITE_DBCONFIG_DQS_DML* = 1013 SQLITE_DBCONFIG_DQS_DDL* = 1014 SQLITE_DBCONFIG_ENABLE_VIEW* = 1015 SQLITE_DBCONFIG_LEGACY_FILE_FORMAT* = 1016 SQLITE_DBCONFIG_TRUSTED_SCHEMA* = 1017 SQLITE_DBCONFIG_MAX* = 1017 # # ** 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. # SQLITE_DENY* = 1 SQLITE_IGNORE* = 2 # # ** 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 ********** SQLITE_CREATE_INDEX* = 1 SQLITE_CREATE_TABLE* = 2 SQLITE_CREATE_TEMP_INDEX* = 3 SQLITE_CREATE_TEMP_TABLE* = 4 SQLITE_CREATE_TEMP_TRIGGER* = 5 SQLITE_CREATE_TEMP_VIEW* = 6 SQLITE_CREATE_TRIGGER* = 7 SQLITE_CREATE_VIEW* = 8 SQLITE_DELETE* = 9 SQLITE_DROP_INDEX* = 10 SQLITE_DROP_TABLE* = 11 SQLITE_DROP_TEMP_INDEX* = 12 SQLITE_DROP_TEMP_TABLE* = 13 SQLITE_DROP_TEMP_TRIGGER* = 14 SQLITE_DROP_TEMP_VIEW* = 15 SQLITE_DROP_TRIGGER* = 16 SQLITE_DROP_VIEW* = 17 SQLITE_INSERT* = 18 SQLITE_PRAGMA* = 19 SQLITE_READ* = 20 SQLITE_SELECT* = 21 SQLITE_TRANSACTION* = 22 SQLITE_UPDATE* = 23 SQLITE_ATTACH* = 24 SQLITE_DETACH* = 25 SQLITE_ALTER_TABLE* = 26 SQLITE_REINDEX* = 27 SQLITE_ANALYZE* = 28 SQLITE_CREATE_VTABLE* = 29 SQLITE_DROP_VTABLE* = 30 SQLITE_FUNCTION* = 31 SQLITE_SAVEPOINT* = 32 SQLITE_COPY* = 0 SQLITE_RECURSIVE* = 33 # # ** 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 M argument # ** to [sqlite3_trace_v2(D,M,X,P)] 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. # ** # **
# ** [[SQLITE_TRACE_STMT]]
SQLITE_TRACE_STMT
# **
^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]]
SQLITE_TRACE_PROFILE
# **
^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]]
SQLITE_TRACE_ROW
# **
^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]]
SQLITE_TRACE_CLOSE
# **
^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. # **
# SQLITE_TRACE_STMT* = 0x01 SQLITE_TRACE_PROFILE* = 0x02 SQLITE_TRACE_ROW* = 0x04 SQLITE_TRACE_CLOSE* = 0x08 # # ** 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]. # ** # **
# ** [[SQLITE_LIMIT_LENGTH]] ^(
SQLITE_LIMIT_LENGTH
# **
The maximum size of any string or BLOB or table row, in bytes.
)^ # ** # ** [[SQLITE_LIMIT_SQL_LENGTH]] ^(
SQLITE_LIMIT_SQL_LENGTH
# **
The maximum length of an SQL statement, in bytes.
)^ # ** # ** [[SQLITE_LIMIT_COLUMN]] ^(
SQLITE_LIMIT_COLUMN
# **
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.
)^ # ** # ** [[SQLITE_LIMIT_EXPR_DEPTH]] ^(
SQLITE_LIMIT_EXPR_DEPTH
# **
The maximum depth of the parse tree on any expression.
)^ # ** # ** [[SQLITE_LIMIT_COMPOUND_SELECT]] ^(
SQLITE_LIMIT_COMPOUND_SELECT
# **
The maximum number of terms in a compound SELECT statement.
)^ # ** # ** [[SQLITE_LIMIT_VDBE_OP]] ^(
SQLITE_LIMIT_VDBE_OP
# **
The maximum number of instructions in a virtual machine program # ** used to implement an SQL statement. If [sqlite3_prepare_v2()] or # ** the equivalent tries to allocate space for more than this many opcodes # ** in a single prepared statement, an SQLITE_NOMEM error is returned.
)^ # ** # ** [[SQLITE_LIMIT_FUNCTION_ARG]] ^(
SQLITE_LIMIT_FUNCTION_ARG
# **
The maximum number of arguments on a function.
)^ # ** # ** [[SQLITE_LIMIT_ATTACHED]] ^(
SQLITE_LIMIT_ATTACHED
# **
The maximum number of [ATTACH | attached databases].)^
# ** # ** [[SQLITE_LIMIT_LIKE_PATTERN_LENGTH]] # ** ^(
SQLITE_LIMIT_LIKE_PATTERN_LENGTH
# **
The maximum length of the pattern argument to the [LIKE] or # ** [GLOB] operators.
)^ # ** # ** [[SQLITE_LIMIT_VARIABLE_NUMBER]] # ** ^(
SQLITE_LIMIT_VARIABLE_NUMBER
# **
The maximum index number of any [parameter] in an SQL statement.)^ # ** # ** [[SQLITE_LIMIT_TRIGGER_DEPTH]] ^(
SQLITE_LIMIT_TRIGGER_DEPTH
# **
The maximum depth of recursion for triggers.
)^ # ** # ** [[SQLITE_LIMIT_WORKER_THREADS]] ^(
SQLITE_LIMIT_WORKER_THREADS
# **
The maximum number of auxiliary worker threads that a single # ** [prepared statement] may start.
)^ # **
# SQLITE_LIMIT_LENGTH* = 0 SQLITE_LIMIT_SQL_LENGTH* = 1 SQLITE_LIMIT_COLUMN* = 2 SQLITE_LIMIT_EXPR_DEPTH* = 3 SQLITE_LIMIT_COMPOUND_SELECT* = 4 SQLITE_LIMIT_VDBE_OP* = 5 SQLITE_LIMIT_FUNCTION_ARG* = 6 SQLITE_LIMIT_ATTACHED* = 7 SQLITE_LIMIT_LIKE_PATTERN_LENGTH* = 8 SQLITE_LIMIT_VARIABLE_NUMBER* = 9 SQLITE_LIMIT_TRIGGER_DEPTH* = 10 SQLITE_LIMIT_WORKER_THREADS* = 11 # # ** CAPI3REF: Prepare Flags # ** # ** These constants define various flags that can be passed into # ** "prepFlags" parameter of the [sqlite3_prepare_v3()] and # ** [sqlite3_prepare16_v3()] interfaces. # ** # ** New flags may be added in future releases of SQLite. # ** # **
# ** [[SQLITE_PREPARE_PERSISTENT]] ^(
SQLITE_PREPARE_PERSISTENT
# **
The SQLITE_PREPARE_PERSISTENT flag is a hint to the query planner # ** that the prepared statement will be retained for a long time and # ** probably reused many times.)^ ^Without this flag, [sqlite3_prepare_v3()] # ** and [sqlite3_prepare16_v3()] assume that the prepared statement will # ** be used just once or at most a few times and then destroyed using # ** [sqlite3_finalize()] relatively soon. The current implementation acts # ** on this hint by avoiding the use of [lookaside memory] so as not to # ** deplete the limited store of lookaside memory. Future versions of # ** SQLite may act on this hint differently. # ** # ** [[SQLITE_PREPARE_NORMALIZE]]
SQLITE_PREPARE_NORMALIZE
# **
The SQLITE_PREPARE_NORMALIZE flag is a no-op. This flag used # ** to be required for any prepared statement that wanted to use the # ** [sqlite3_normalized_sql()] interface. However, the # ** [sqlite3_normalized_sql()] interface is now available to all # ** prepared statements, regardless of whether or not they use this # ** flag. # ** # ** [[SQLITE_PREPARE_NO_VTAB]]
SQLITE_PREPARE_NO_VTAB
# **
The SQLITE_PREPARE_NO_VTAB flag causes the SQL compiler # ** to return an error (error code SQLITE_ERROR) if the statement uses # ** any virtual tables. # **
# SQLITE_PREPARE_PERSISTENT* = 0x01 SQLITE_PREPARE_NORMALIZE* = 0x02 SQLITE_PREPARE_NO_VTAB* = 0x04 # # ** CAPI3REF: Fundamental Datatypes # ** KEYWORDS: SQLITE_TEXT # ** # ** ^(Every value in SQLite has one of five fundamental datatypes: # ** # ** )^ # ** # ** 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. # SQLITE_INTEGER* = 1 SQLITE_FLOAT* = 2 SQLITE_BLOB* = 4 SQLITE_NULL* = 5 SQLITE_TEXT* = 3 SQLITE3_TEXT* = 3 # # ** CAPI3REF: Text Encodings # ** # ** These constant define integer codes that represent the various # ** text encodings supported by SQLite. # SQLITE_UTF8* = 1 SQLITE_UTF16LE* = 2 SQLITE_UTF16BE* = 3 SQLITE_UTF16* = 4 SQLITE_ANY* = 5 SQLITE_UTF16_ALIGNED* = 8 # # ** 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()]. # ** # **
# ** [[SQLITE_DETERMINISTIC]]
SQLITE_DETERMINISTIC
# ** The SQLITE_DETERMINISTIC flag means that the new function always gives # ** the same output when the input parameters are the same. # ** The [abs|abs() function] is deterministic, for example, but # ** [randomblob|randomblob()] is not. Functions must # ** be deterministic in order to be used in certain contexts such as # ** with the WHERE clause of [partial indexes] or in [generated columns]. # ** SQLite might also optimize deterministic functions by factoring them # ** out of inner loops. # **
# ** # ** [[SQLITE_DIRECTONLY]]
SQLITE_DIRECTONLY
# ** The SQLITE_DIRECTONLY flag means that the function may only be invoked # ** from top-level SQL, and cannot be used in VIEWs or TRIGGERs nor in # ** schema structures such as [CHECK constraints], [DEFAULT clauses], # ** [expression indexes], [partial indexes], or [generated columns]. # ** The SQLITE_DIRECTONLY flags is a security feature which is recommended # ** for all [application-defined SQL functions], and especially for functions # ** that have side-effects or that could potentially leak sensitive # ** information. # **
# ** # ** [[SQLITE_INNOCUOUS]]
SQLITE_INNOCUOUS
# ** The SQLITE_INNOCUOUS flag means that the function is unlikely # ** to cause problems even if misused. An innocuous function should have # ** no side effects and should not depend on any values other than its # ** input parameters. The [abs|abs() function] is an example of an # ** innocuous function. # ** The [load_extension() SQL function] is not innocuous because of its # ** side effects. # **

SQLITE_INNOCUOUS is similar to SQLITE_DETERMINISTIC, but is not # ** exactly the same. The [random|random() function] is an example of a # ** function that is innocuous but not deterministic. # **

Some heightened security settings # ** ([SQLITE_DBCONFIG_TRUSTED_SCHEMA] and [PRAGMA trusted_schema=OFF]) # ** disable the use of SQL functions inside views and triggers and in # ** schema structures such as [CHECK constraints], [DEFAULT clauses], # ** [expression indexes], [partial indexes], and [generated columns] unless # ** the function is tagged with SQLITE_INNOCUOUS. Most built-in functions # ** are innocuous. Developers are advised to avoid using the # ** SQLITE_INNOCUOUS flag for application-defined functions unless the # ** function has been carefully audited and found to be free of potentially # ** security-adverse side-effects and information-leaks. # **

# ** # ** [[SQLITE_SUBTYPE]]
SQLITE_SUBTYPE
# ** The SQLITE_SUBTYPE flag indicates to SQLite that a function may call # ** [sqlite3_value_subtype()] to inspect the sub-types of its arguments. # ** Specifying this flag makes no difference for scalar or aggregate user # ** functions. However, if it is not specified for a user-defined window # ** function, then any sub-types belonging to arguments passed to the window # ** function may be discarded before the window function is called (i.e. # ** sqlite3_value_subtype() will always return 0). # **
# **
# SQLITE_DETERMINISTIC* = 0x000000800 SQLITE_DIRECTONLY* = 0x000080000 SQLITE_SUBTYPE* = 0x000100000 SQLITE_INNOCUOUS* = 0x000200000 # # ** CAPI3REF: Win32 Directory Types # ** # ** These macros are only available on Windows. They define the allowed values # ** for the type argument to the [sqlite3_win32_set_directory] interface. # SQLITE_WIN32_DATA_DIRECTORY_TYPE* = 1 SQLITE_WIN32_TEMP_DIRECTORY_TYPE* = 2 # # ** CAPI3REF: Allowed return values from [sqlite3_txn_state()] # ** KEYWORDS: {transaction state} # ** # ** These constants define the current transaction state of a database file. # ** ^The [sqlite3_txn_state(D,S)] interface returns one of these # ** constants in order to describe the transaction state of schema S # ** in [database connection] D. # ** # **
# ** [[SQLITE_TXN_NONE]]
SQLITE_TXN_NONE
# **
The SQLITE_TXN_NONE state means that no transaction is currently # ** pending.
# ** # ** [[SQLITE_TXN_READ]]
SQLITE_TXN_READ
# **
The SQLITE_TXN_READ state means that the database is currently # ** in a read transaction. Content has been read from the database file # ** but nothing in the database file has changed. The transaction state # ** will advanced to SQLITE_TXN_WRITE if any changes occur and there are # ** no other conflicting concurrent write transactions. The transaction # ** state will revert to SQLITE_TXN_NONE following a [ROLLBACK] or # ** [COMMIT].
# ** # ** [[SQLITE_TXN_WRITE]]
SQLITE_TXN_WRITE
# **
The SQLITE_TXN_WRITE state means that the database is currently # ** in a write transaction. Content has been written to the database file # ** but has not yet committed. The transaction state will change to # ** to SQLITE_TXN_NONE at the next [ROLLBACK] or [COMMIT].
# SQLITE_TXN_NONE* = 0 SQLITE_TXN_READ* = 1 SQLITE_TXN_WRITE* = 2 # # ** CAPI3REF: Virtual Table Scan Flags # ** # ** Virtual table implementations are allowed to set the # ** [sqlite3_index_info].idxFlags field to some combination of # ** these bits. # SQLITE_INDEX_SCAN_UNIQUE* = 1 # # ** CAPI3REF: Virtual Table Constraint Operator Codes # ** # ** These macros define 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]. # SQLITE_INDEX_CONSTRAINT_EQ* = 2 SQLITE_INDEX_CONSTRAINT_GT* = 4 SQLITE_INDEX_CONSTRAINT_LE* = 8 SQLITE_INDEX_CONSTRAINT_LT* = 16 SQLITE_INDEX_CONSTRAINT_GE* = 32 SQLITE_INDEX_CONSTRAINT_MATCH* = 64 SQLITE_INDEX_CONSTRAINT_LIKE* = 65 SQLITE_INDEX_CONSTRAINT_GLOB* = 66 SQLITE_INDEX_CONSTRAINT_REGEXP* = 67 SQLITE_INDEX_CONSTRAINT_NE* = 68 SQLITE_INDEX_CONSTRAINT_ISNOT* = 69 SQLITE_INDEX_CONSTRAINT_ISNOTNULL* = 70 SQLITE_INDEX_CONSTRAINT_ISNULL* = 71 SQLITE_INDEX_CONSTRAINT_IS* = 72 SQLITE_INDEX_CONSTRAINT_FUNCTION* = 150 # # ** 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. # SQLITE_MUTEX_FAST* = 0 SQLITE_MUTEX_RECURSIVE* = 1 SQLITE_MUTEX_STATIC_MAIN* = 2 SQLITE_MUTEX_STATIC_MEM* = 3 SQLITE_MUTEX_STATIC_MEM2* = 4 SQLITE_MUTEX_STATIC_OPEN* = 4 SQLITE_MUTEX_STATIC_PRNG* = 5 SQLITE_MUTEX_STATIC_LRU* = 6 SQLITE_MUTEX_STATIC_LRU2* = 7 SQLITE_MUTEX_STATIC_PMEM* = 7 SQLITE_MUTEX_STATIC_APP1* = 8 SQLITE_MUTEX_STATIC_APP2* = 9 SQLITE_MUTEX_STATIC_APP3* = 10 SQLITE_MUTEX_STATIC_VFS1* = 11 SQLITE_MUTEX_STATIC_VFS2* = 12 SQLITE_MUTEX_STATIC_VFS3* = 13 # Legacy compatibility: SQLITE_MUTEX_STATIC_MASTER* = 2 # # ** 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. # SQLITE_TESTCTRL_FIRST* = 5 SQLITE_TESTCTRL_PRNG_SAVE* = 5 SQLITE_TESTCTRL_PRNG_RESTORE* = 6 SQLITE_TESTCTRL_PRNG_RESET* = 7 SQLITE_TESTCTRL_BITVEC_TEST* = 8 SQLITE_TESTCTRL_FAULT_INSTALL* = 9 SQLITE_TESTCTRL_BENIGN_MALLOC_HOOKS* = 10 SQLITE_TESTCTRL_PENDING_BYTE* = 11 SQLITE_TESTCTRL_ASSERT* = 12 SQLITE_TESTCTRL_ALWAYS* = 13 SQLITE_TESTCTRL_RESERVE* = 14 SQLITE_TESTCTRL_OPTIMIZATIONS* = 15 SQLITE_TESTCTRL_ISKEYWORD* = 16 SQLITE_TESTCTRL_SCRATCHMALLOC* = 17 SQLITE_TESTCTRL_INTERNAL_FUNCTIONS* = 17 SQLITE_TESTCTRL_LOCALTIME_FAULT* = 18 SQLITE_TESTCTRL_EXPLAIN_STMT* = 19 SQLITE_TESTCTRL_ONCE_RESET_THRESHOLD* = 19 SQLITE_TESTCTRL_NEVER_CORRUPT* = 20 SQLITE_TESTCTRL_VDBE_COVERAGE* = 21 SQLITE_TESTCTRL_BYTEORDER* = 22 SQLITE_TESTCTRL_ISINIT* = 23 SQLITE_TESTCTRL_SORTER_MMAP* = 24 SQLITE_TESTCTRL_IMPOSTER* = 25 SQLITE_TESTCTRL_PARSER_COVERAGE* = 26 SQLITE_TESTCTRL_RESULT_INTREAL* = 27 SQLITE_TESTCTRL_PRNG_SEED* = 28 SQLITE_TESTCTRL_EXTRA_SCHEMA_CHECKS* = 29 SQLITE_TESTCTRL_SEEK_COUNT* = 30 SQLITE_TESTCTRL_LAST* = 30 # # ** CAPI3REF: Status Parameters # ** KEYWORDS: {status parameters} # ** # ** These integer constants designate various run-time status parameters # ** that can be returned by [sqlite3_status()]. # ** # **
# ** [[SQLITE_STATUS_MEMORY_USED]] ^(
SQLITE_STATUS_MEMORY_USED
# **
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. 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].
)^ # ** # ** [[SQLITE_STATUS_MALLOC_SIZE]] ^(
SQLITE_STATUS_MALLOC_SIZE
# **
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.
)^ # ** # ** [[SQLITE_STATUS_MALLOC_COUNT]] ^(
SQLITE_STATUS_MALLOC_COUNT
# **
This parameter records the number of separate memory allocations # ** currently checked out.
)^ # ** # ** [[SQLITE_STATUS_PAGECACHE_USED]] ^(
SQLITE_STATUS_PAGECACHE_USED
# **
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.
)^ # ** # ** [[SQLITE_STATUS_PAGECACHE_OVERFLOW]] # ** ^(
SQLITE_STATUS_PAGECACHE_OVERFLOW
# **
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.
)^ # ** # ** [[SQLITE_STATUS_PAGECACHE_SIZE]] ^(
SQLITE_STATUS_PAGECACHE_SIZE
# **
This parameter records the largest memory allocation request # ** handed to the [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.
)^ # ** # ** [[SQLITE_STATUS_SCRATCH_USED]]
SQLITE_STATUS_SCRATCH_USED
# **
No longer used.
# ** # ** [[SQLITE_STATUS_SCRATCH_OVERFLOW]] ^(
SQLITE_STATUS_SCRATCH_OVERFLOW
# **
No longer used.
# ** # ** [[SQLITE_STATUS_SCRATCH_SIZE]]
SQLITE_STATUS_SCRATCH_SIZE
# **
No longer used.
# ** # ** [[SQLITE_STATUS_PARSER_STACK]] ^(
SQLITE_STATUS_PARSER_STACK
# **
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].
)^ # **
# ** # ** New status parameters may be added from time to time. # SQLITE_STATUS_MEMORY_USED* = 0 SQLITE_STATUS_PAGECACHE_USED* = 1 SQLITE_STATUS_PAGECACHE_OVERFLOW* = 2 SQLITE_STATUS_SCRATCH_USED* = 3 SQLITE_STATUS_SCRATCH_OVERFLOW* = 4 SQLITE_STATUS_MALLOC_SIZE* = 5 SQLITE_STATUS_PARSER_STACK* = 6 SQLITE_STATUS_PAGECACHE_SIZE* = 7 SQLITE_STATUS_SCRATCH_SIZE* = 8 SQLITE_STATUS_MALLOC_COUNT* = 9 # # ** 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. # ** # **
# ** [[SQLITE_DBSTATUS_LOOKASIDE_USED]] ^(
SQLITE_DBSTATUS_LOOKASIDE_USED
# **
This parameter returns the number of lookaside memory slots currently # ** checked out.
)^ # ** # ** [[SQLITE_DBSTATUS_LOOKASIDE_HIT]] ^(
SQLITE_DBSTATUS_LOOKASIDE_HIT
# **
This parameter returns the number of 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]] # ** ^(
SQLITE_DBSTATUS_LOOKASIDE_MISS_SIZE
# **
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]] # ** ^(
SQLITE_DBSTATUS_LOOKASIDE_MISS_FULL
# **
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]] ^(
SQLITE_DBSTATUS_CACHE_USED
# **
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]] # ** ^(
SQLITE_DBSTATUS_CACHE_USED_SHARED
# **
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]] ^(
SQLITE_DBSTATUS_SCHEMA_USED
# **
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]] ^(
SQLITE_DBSTATUS_STMT_USED
# **
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. # **
# ** # ** [[SQLITE_DBSTATUS_CACHE_HIT]] ^(
SQLITE_DBSTATUS_CACHE_HIT
# **
This parameter returns the number of pager cache hits that have # ** occurred.)^ ^The highwater mark associated with SQLITE_DBSTATUS_CACHE_HIT # ** is always 0. # **
# ** # ** [[SQLITE_DBSTATUS_CACHE_MISS]] ^(
SQLITE_DBSTATUS_CACHE_MISS
# **
This parameter returns the number of pager cache misses that have # ** occurred.)^ ^The highwater mark associated with SQLITE_DBSTATUS_CACHE_MISS # ** is always 0. # **
# ** # ** [[SQLITE_DBSTATUS_CACHE_WRITE]] ^(
SQLITE_DBSTATUS_CACHE_WRITE
# **
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. # **
# ** # ** [[SQLITE_DBSTATUS_CACHE_SPILL]] ^(
SQLITE_DBSTATUS_CACHE_SPILL
# **
This parameter returns the number of dirty cache entries that have # ** been written to disk in the middle of a transaction due to the page # ** cache overflowing. Transactions are more efficient if they are written # ** to disk all at once. When pages spill mid-transaction, that introduces # ** additional overhead. This parameter can be used help identify # ** inefficiencies that can be resolved by increasing the cache size. # **
# ** # ** [[SQLITE_DBSTATUS_DEFERRED_FKS]] ^(
SQLITE_DBSTATUS_DEFERRED_FKS
# **
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. # **
# **
# SQLITE_DBSTATUS_LOOKASIDE_USED* = 0 SQLITE_DBSTATUS_CACHE_USED* = 1 SQLITE_DBSTATUS_SCHEMA_USED* = 2 SQLITE_DBSTATUS_STMT_USED* = 3 SQLITE_DBSTATUS_LOOKASIDE_HIT* = 4 SQLITE_DBSTATUS_LOOKASIDE_MISS_SIZE* = 5 SQLITE_DBSTATUS_LOOKASIDE_MISS_FULL* = 6 SQLITE_DBSTATUS_CACHE_HIT* = 7 SQLITE_DBSTATUS_CACHE_MISS* = 8 SQLITE_DBSTATUS_CACHE_WRITE* = 9 SQLITE_DBSTATUS_DEFERRED_FKS* = 10 SQLITE_DBSTATUS_CACHE_USED_SHARED* = 11 SQLITE_DBSTATUS_CACHE_SPILL* = 12 SQLITE_DBSTATUS_MAX* = 12 # # ** 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: # ** # **
# ** [[SQLITE_STMTSTATUS_FULLSCAN_STEP]]
SQLITE_STMTSTATUS_FULLSCAN_STEP
# **
^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.
# ** # ** [[SQLITE_STMTSTATUS_SORT]]
SQLITE_STMTSTATUS_SORT
# **
^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.
# ** # ** [[SQLITE_STMTSTATUS_AUTOINDEX]]
SQLITE_STMTSTATUS_AUTOINDEX
# **
^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.
# ** # ** [[SQLITE_STMTSTATUS_VM_STEP]]
SQLITE_STMTSTATUS_VM_STEP
# **
^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. # ** # ** [[SQLITE_STMTSTATUS_REPREPARE]]
SQLITE_STMTSTATUS_REPREPARE
# **
^This is the number of times that the prepare statement has been # ** automatically regenerated due to schema changes or changes to # ** [bound parameters] that might affect the query plan. # ** # ** [[SQLITE_STMTSTATUS_RUN]]
SQLITE_STMTSTATUS_RUN
# **
^This is the number of times that the prepared statement has # ** been run. A single "run" for the purposes of this counter is one # ** or more calls to [sqlite3_step()] followed by a call to [sqlite3_reset()]. # ** The counter is incremented on the first [sqlite3_step()] call of each # ** cycle. # ** # ** [[SQLITE_STMTSTATUS_MEMUSED]]
SQLITE_STMTSTATUS_MEMUSED
# **
^This is the approximate number of bytes of heap memory # ** used to store the prepared statement. ^This value is not actually # ** a counter, and so the resetFlg parameter to sqlite3_stmt_status() # ** is ignored when the opcode is SQLITE_STMTSTATUS_MEMUSED. # **
# **
# SQLITE_STMTSTATUS_FULLSCAN_STEP* = 1 SQLITE_STMTSTATUS_SORT* = 2 SQLITE_STMTSTATUS_AUTOINDEX* = 3 SQLITE_STMTSTATUS_VM_STEP* = 4 SQLITE_STMTSTATUS_REPREPARE* = 5 SQLITE_STMTSTATUS_RUN* = 6 SQLITE_STMTSTATUS_MEMUSED* = 99 # # ** 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. # SQLITE_CHECKPOINT_PASSIVE* = 0 SQLITE_CHECKPOINT_FULL* = 1 SQLITE_CHECKPOINT_RESTART* = 2 SQLITE_CHECKPOINT_TRUNCATE* = 3 # # ** CAPI3REF: Virtual Table Configuration Options # ** KEYWORDS: {virtual table configuration options} # ** KEYWORDS: {virtual table configuration option} # ** # ** These macros define the various options to the # ** [sqlite3_vtab_config()] interface that [virtual table] implementations # ** can use to customize and optimize their behavior. # ** # **
# ** [[SQLITE_VTAB_CONSTRAINT_SUPPORT]] # **
SQLITE_VTAB_CONSTRAINT_SUPPORT
# **
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. # **
# ** # ** [[SQLITE_VTAB_DIRECTONLY]]
SQLITE_VTAB_DIRECTONLY
# **
Calls of the form # ** [sqlite3_vtab_config](db,SQLITE_VTAB_DIRECTONLY) from within the # ** the [xConnect] or [xCreate] methods of a [virtual table] implmentation # ** prohibits that virtual table from being used from within triggers and # ** views. # **
# ** # ** [[SQLITE_VTAB_INNOCUOUS]]
SQLITE_VTAB_INNOCUOUS
# **
Calls of the form # ** [sqlite3_vtab_config](db,SQLITE_VTAB_INNOCUOUS) from within the # ** the [xConnect] or [xCreate] methods of a [virtual table] implmentation # ** identify that virtual table as being safe to use from within triggers # ** and views. Conceptually, the SQLITE_VTAB_INNOCUOUS tag means that the # ** virtual table can do no serious harm even if it is controlled by a # ** malicious hacker. Developers should avoid setting the SQLITE_VTAB_INNOCUOUS # ** flag unless absolutely necessary. # **
# **
# SQLITE_VTAB_CONSTRAINT_SUPPORT* = 1 SQLITE_VTAB_INNOCUOUS* = 2 SQLITE_VTAB_DIRECTONLY* = 3 # # ** 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]. # SQLITE_ROLLBACK* = 1 # #define SQLITE_IGNORE 2 Also used by sqlite3_authorizer() callback SQLITE_FAIL* = 3 # #define SQLITE_ABORT 4 Also an error code 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. # ** # **
# ** [[SQLITE_SCANSTAT_NLOOP]]
SQLITE_SCANSTAT_NLOOP
# **
^The [sqlite3_int64] variable pointed to by the V parameter will be # ** set to the total number of times that the X-th loop has run.
# ** # ** [[SQLITE_SCANSTAT_NVISIT]]
SQLITE_SCANSTAT_NVISIT
# **
^The [sqlite3_int64] variable pointed to by the V parameter will be set # ** to the total number of rows examined by all iterations of the X-th loop.
# ** # ** [[SQLITE_SCANSTAT_EST]]
SQLITE_SCANSTAT_EST
# **
^The "double" variable pointed to by the V 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]]
SQLITE_SCANSTAT_NAME
# **
^The "const char *" variable pointed to by the V 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]]
SQLITE_SCANSTAT_EXPLAIN
# **
^The "const char *" variable pointed to by the V 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]]
SQLITE_SCANSTAT_SELECT
# **
^The "int" variable pointed to by the V 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. # **
# SQLITE_SCANSTAT_NLOOP* = 0 SQLITE_SCANSTAT_NVISIT* = 1 SQLITE_SCANSTAT_EST* = 2 SQLITE_SCANSTAT_NAME* = 3 SQLITE_SCANSTAT_EXPLAIN* = 4 SQLITE_SCANSTAT_SELECTID* = 5 # # ** CAPI3REF: Flags for sqlite3_serialize # ** # ** Zero or more of the following constants can be OR-ed together for # ** the F argument to [sqlite3_serialize(D,S,P,F)]. # ** # ** SQLITE_SERIALIZE_NOCOPY means that [sqlite3_serialize()] will return # ** a pointer to contiguous in-memory database that it is currently using, # ** without making a copy of the database. If SQLite is not currently using # ** a contiguous in-memory database, then this option causes # ** [sqlite3_serialize()] to return a NULL pointer. SQLite will only be # ** using a contiguous in-memory database if it has been initialized by a # ** prior call to [sqlite3_deserialize()]. # SQLITE_SERIALIZE_NOCOPY* = 0x001 # # ** CAPI3REF: Flags for sqlite3_deserialize() # ** # ** The following are allowed values for 6th argument (the F argument) to # ** the [sqlite3_deserialize(D,S,P,N,M,F)] interface. # ** # ** The SQLITE_DESERIALIZE_FREEONCLOSE means that the database serialization # ** in the P argument is held in memory obtained from [sqlite3_malloc64()] # ** and that SQLite should take ownership of this memory and automatically # ** free it when it has finished using it. Without this flag, the caller # ** is responsible for freeing any dynamically allocated memory. # ** # ** The SQLITE_DESERIALIZE_RESIZEABLE flag means that SQLite is allowed to # ** grow the size of the database using calls to [sqlite3_realloc64()]. This # ** flag should only be used if SQLITE_DESERIALIZE_FREEONCLOSE is also used. # ** Without this flag, the deserialized database cannot increase in size beyond # ** the number of bytes specified by the M parameter. # ** # ** The SQLITE_DESERIALIZE_READONLY flag means that the deserialized database # ** should be treated as read-only. # SQLITE_DESERIALIZE_FREEONCLOSE* = 1 SQLITE_DESERIALIZE_RESIZEABLE* = 2 SQLITE_DESERIALIZE_READONLY* = 4 # # ** 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. # # # ** Allowed values for sqlite3_rtree_query.eWithin and .eParentWithin. # NOT_WITHIN* = 0 PARTLY_WITHIN* = 1 FULLY_WITHIN* = 2 # Flags that may be passed as the third argument to xTokenize() FTS5_TOKENIZE_QUERY* = 0x0001 FTS5_TOKENIZE_PREFIX* = 0x0002 FTS5_TOKENIZE_DOCUMENT* = 0x0004 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. FTS5_TOKEN_COLOCATED* = 0x0001 {.pragma: impsqlite3, importc.} {.pragma: impsqlite3C, impsqlite3, cdecl.} type # # ** 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. # sqlite3* {.incompleteStruct.} = object # # ** The type for a callback function. # ** This is legacy and deprecated. It is included for historical # ** compatibility and is not documented. # sqlite3_callback* {.impsqlite3.} = proc(a1: pointer, a2: cint, a3: ptr cstring, a4: ptr cstring): cint {.cdecl.} # # ** 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. # sqlite3_file* {.incompleteStruct.} = object # # ** 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 # ** # ** 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: # ** # ** # ** # ** 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. # sqlite3_io_methods* {.incompleteStruct.} = object # deprecated names # # ** 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()]. # sqlite3_mutex* {.incompleteStruct.} = object # # ** 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. # sqlite3_api_routines* {.incompleteStruct.} = object # # ** 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 VFS interface is sometimes extended by adding new methods onto # ** the end. Each time such an extension occurs, the iVersion field # ** is incremented. The iVersion value started out as 1 in # ** SQLite [version 3.5.0] on [dateof:3.5.0], then increased to 2 # ** with SQLite [version 3.7.0] on [dateof:3.7.0], and then increased # ** to 3 with SQLite [version 3.7.6] on [dateof:3.7.6]. Additional fields # ** may be appended to the sqlite3_vfs object and the iVersion value # ** may increase again in future versions of SQLite. # ** Note that due to an oversight, the structure # ** of the sqlite3_vfs object changed in the transition from # ** SQLite [version 3.5.9] to [version 3.6.0] on [dateof:3.6.0] # ** and yet the iVersion field was not increased. # ** # ** 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: # ** # ** )^ # ** # ** 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: # ** # ** # ** # ** 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 not 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 SQLITE_ACCESS_READ # ** flag is never actually used and is not implemented in the built-in # ** VFSes of SQLite. The file is named by the second argument and can be a # ** directory. The xAccess method returns [SQLITE_OK] on success or some # ** non-zero error code if there is an I/O error or if the name of # ** the file given in the second argument is illegal. If SQLITE_OK # ** is returned, then non-zero or zero is written into *pResOut to indicate # ** whether or not the file is accessible. # ** # ** ^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. # sqlite3_vfs* {.incompleteStruct.} = object sqlite3_syscall_ptr* {.impsqlite3.} = proc() {.cdecl.} # Type 'sqlite3_vfs' skipped # Type 'sqlite3_vfs' skipped # Type 'sqlite3_vfs' skipped # Type 'sqlite3_file' skipped # Type 'sqlite3_vfs' skipped # Type 'sqlite3_vfs' skipped # Type 'sqlite3_vfs' skipped # Type 'sqlite3_vfs' skipped # Type 'sqlite3_vfs' skipped # Type 'sqlite3_vfs' skipped # Type 'sqlite3_vfs' skipped # Type 'sqlite3_vfs' skipped # Type 'sqlite3_file' skipped # Type 'sqlite3_vfs' skipped # Type 'sqlite3_vfs' skipped # Type 'sqlite3_vfs' skipped # Type 'sqlite3_vfs' skipped # Type 'sqlite3_vfs' skipped # Type 'sqlite3_vfs' skipped # Type 'sqlite3_vfs' skipped # Type 'sqlite3_vfs' skipped # Type 'sqlite3_vfs' skipped # Type 'sqlite3_vfs' skipped # Type 'sqlite3_vfs' skipped # Type 'sqlite3_vfs' skipped # Type 'sqlite3_int64' skipped # Type 'sqlite3_vfs' skipped # Type 'sqlite3_syscall_ptr' skipped # Type 'sqlite3_syscall_ptr' skipped # Type 'sqlite3_vfs' skipped # Type 'sqlite3_vfs' skipped # # ** 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 required 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_MAIN] 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(). # sqlite3_mem_methods* {.incompleteStruct.} = object # # ** 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: # ** # **
    # **
  1. Create the prepared statement object using [sqlite3_prepare_v2()]. # **
  2. Bind values to [parameters] using the sqlite3_bind_*() # ** interfaces. # **
  3. Run the SQL by calling [sqlite3_step()] one or more times. # **
  4. Reset the prepared statement using [sqlite3_reset()] then go back # ** to step 2. Do this zero or more times. # **
  5. Destroy the object using [sqlite3_finalize()]. # **
# sqlite3_stmt* {.incompleteStruct.} = object # # ** 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 as arguments # ** to [sqlite3_result_value()], [sqlite3_bind_value()], and # ** [sqlite3_value_dup()]. # ** The [sqlite3_value_blob | sqlite3_value_type()] family of # ** interfaces require protected sqlite3_value objects. # sqlite3_value* {.incompleteStruct.} = object # # ** 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()]. # sqlite3_context* {.incompleteStruct.} = object # # ** 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. # sqlite3_destructor_type* {.impsqlite3.} = proc(a1: pointer) {.cdecl.} # # ** 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 # sqlite3_vtab* {.incompleteStruct.} = object sqlite3_index_info* {.incompleteStruct.} = object sqlite3_vtab_cursor* {.incompleteStruct.} = object sqlite3_module* {.incompleteStruct.} = object # # ** CAPI3REF: Virtual Table Object # ** KEYWORDS: sqlite3_module {virtual table module} # ** # ** This structure, sometimes called a "virtual table module", # ** defines the implementation of a [virtual table]. # ** 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. # # Type 'sqlite3_module' skipped # Type 'sqlite3' skipped # Type 'sqlite3_vtab' skipped # Type 'sqlite3' skipped # Type 'sqlite3_vtab' skipped # Type 'sqlite3_vtab' skipped # Type 'sqlite3_index_info' skipped # Type 'sqlite3_vtab' skipped # Type 'sqlite3_vtab' skipped # Type 'sqlite3_vtab' skipped # Type 'sqlite3_vtab_cursor' skipped # Type 'sqlite3_vtab_cursor' skipped # Type 'sqlite3_vtab_cursor' skipped # Type 'sqlite3_value' skipped # Type 'sqlite3_vtab_cursor' skipped # Type 'sqlite3_vtab_cursor' skipped # Type 'sqlite3_vtab_cursor' skipped # Type 'sqlite3_context' skipped # Type 'sqlite3_vtab_cursor' skipped # Type 'sqlite3_int64' skipped # Type 'sqlite3_vtab' skipped # Type 'sqlite3_value' skipped # Type 'sqlite3_int64' skipped # Type 'sqlite3_vtab' skipped # Type 'sqlite3_vtab' skipped # Type 'sqlite3_vtab' skipped # Type 'sqlite3_vtab' skipped # Type 'sqlite3_vtab' skipped # Type 'sqlite3_module' skipped # Type 'sqlite3' skipped # Type 'sqlite3_vtab' skipped # Type 'sqlite3' skipped # Type 'sqlite3_vtab' skipped # Type 'sqlite3_vtab' skipped # Type 'sqlite3_index_info' skipped # Type 'sqlite3_vtab' skipped # Type 'sqlite3_vtab' skipped # Type 'sqlite3_vtab' skipped # Type 'sqlite3_vtab_cursor' skipped # Type 'sqlite3_vtab_cursor' skipped # Type 'sqlite3_vtab_cursor' skipped # Type 'sqlite3_value' skipped # Type 'sqlite3_vtab_cursor' skipped # Type 'sqlite3_vtab_cursor' skipped # Type 'sqlite3_vtab_cursor' skipped # Type 'sqlite3_context' skipped # Type 'sqlite3_vtab_cursor' skipped # Type 'sqlite3_int64' skipped # Type 'sqlite3_vtab' skipped # Type 'sqlite3_value' skipped # Type 'sqlite3_int64' skipped # Type 'sqlite3_vtab' skipped # Type 'sqlite3_vtab' skipped # Type 'sqlite3_vtab' skipped # Type 'sqlite3_vtab' skipped # Type 'sqlite3_vtab' skipped # Type 'sqlite3_context' skipped # Type 'sqlite3_value' skipped # Type 'sqlite3_vtab' skipped # Type 'sqlite3_vtab' skipped # Type 'sqlite3_vtab' skipped # Type 'sqlite3_vtab' skipped # # ** 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: # ** # **
column OP expr
# ** # ** 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 might not be checked again by the byte code.)^ ^(The # ** aConstraintUsage[].omit flag is an optimization hint. When the omit flag # ** is left in its default setting of false, the constraint will always be # ** checked separately in byte code. If the omit flag is change to true, then # ** the constraint may or may not be checked in byte code. In other words, # ** when the omit flag is true there is no guarantee that the constraint will # ** not be checked again using byte code.)^ # ** # ** ^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 include 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. # # Type 'sqlite3_index_info' skipped # Type 'sqlite3_index_info' skipped # Type 'sqlite3_index_constraint' skipped # Type 'sqlite3_index_orderby' skipped # Type 'sqlite3_index_constraint_usage' skipped # Type 'sqlite3_int64' skipped # Type 'sqlite3_uint64' skipped # # ** 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. # sqlite3_blob* {.incompleteStruct.} = object # # ** 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): # ** # ** )^ # ** # ** 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. # sqlite3_mutex_methods* {.incompleteStruct.} = object # # ** CAPI3REF: Dynamic String Object # ** KEYWORDS: {dynamic string} # ** # ** An instance of the sqlite3_str object contains a dynamically-sized # ** string under construction. # ** # ** The lifecycle of an sqlite3_str object is as follows: # **
    # **
  1. ^The sqlite3_str object is created using [sqlite3_str_new()]. # **
  2. ^Text is appended to the sqlite3_str object using various # ** methods, such as [sqlite3_str_appendf()]. # **
  3. ^The sqlite3_str object is destroyed and the string it created # ** is returned using the [sqlite3_str_finish()] interface. # **
# sqlite3_str* {.incompleteStruct.} = object # # ** 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. # sqlite3_pcache* {.incompleteStruct.} = object # # ** 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. # sqlite3_pcache_page* {.incompleteStruct.} = object # # ** 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: # ** # ** # **
createFlag Behavior when page is not already in cache # **
0 Do not allocate a new page. Return NULL. # **
1 Allocate a new page if it easy and convenient to do so. # ** Otherwise return NULL. # **
2 Make every effort to allocate a new page. Only return # ** NULL if allocating a new page is effectively impossible. # **
# ** # ** ^(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 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. # sqlite3_pcache_methods2* {.incompleteStruct.} = object # # ** 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. # sqlite3_pcache_methods* {.incompleteStruct.} = object # # ** 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] # sqlite3_backup* {.incompleteStruct.} = object # # ** CAPI3REF: Database Snapshot # ** KEYWORDS: {snapshot} {sqlite3_snapshot} # ** # ** 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. # sqlite3_snapshot* {.importc: "struct sqlite3_snapshot", bycopy.} = object hidden*: array[48, cuchar] # # ** Undo the hack that converts floating point types to integer for # ** builds on processors without floating point support. # # End of the 'extern "C"' block # ******* 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. # ** # ************************************************************************* # sqlite3_rtree_geometry* {.incompleteStruct.} = object sqlite3_rtree_query_info* {.incompleteStruct.} = object # The double-precision datatype used by RTree depends on the # ** SQLITE_RTREE_INT_ONLY compile-time option. # sqlite3_rtree_dbl* {.impsqlite3.} = cdouble # end of the 'extern "C"' block # ******* End of sqlite3rtree.h ******** # ******* Begin file sqlite3session.h ******** # ******* 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. # # ************************************************************************ # ** CUSTOM AUXILIARY FUNCTIONS # ** # ** Virtual table implementations may overload SQL functions by implementing # ** the sqlite3_module.xFindFunction() method. # Fts5ExtensionApi* {.incompleteStruct.} = object Fts5Context* {.incompleteStruct.} = object Fts5PhraseIter* {.incompleteStruct.} = object fts5_extension_function* {.impsqlite3.} = proc(pApi: ptr Fts5ExtensionApi, pFts: ptr Fts5Context, pCtx: ptr sqlite3_context, nVal: cint, apVal: ptr ptr sqlite3_value) {.cdecl.} # # ** 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. 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 function's # ** "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 # ** 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, # ** 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. # # Type 'Fts5ExtensionApi' skipped # Type 'Fts5Context' skipped # Type 'Fts5Context' skipped # Type 'Fts5Context' skipped # Type 'sqlite3_int64' skipped # Type 'Fts5Context' skipped # Type 'sqlite3_int64' skipped # Type 'Fts5Context' skipped # Type 'Fts5ExtensionApi' skipped # Type 'Fts5Context' skipped # Type 'Fts5Context' skipped # Type 'Fts5Context' skipped # Type 'sqlite3_int64' skipped # Type 'Fts5Context' skipped # Type 'sqlite3_int64' skipped # Type 'Fts5Context' skipped # Type 'Fts5Context' skipped # Type 'Fts5Context' skipped # Type 'Fts5Context' skipped # Type 'Fts5Context' skipped # Type 'sqlite3_int64' skipped # Type 'Fts5Context' skipped # Type 'Fts5Context' skipped # Type 'Fts5Context' skipped # Type 'Fts5Context' skipped # Type 'Fts5ExtensionApi' skipped # Type 'Fts5Context' skipped # Type 'Fts5Context' skipped # Type 'Fts5Context' skipped # Type 'Fts5Context' skipped # Type 'Fts5PhraseIter' skipped # Type 'Fts5Context' skipped # Type 'Fts5PhraseIter' skipped # Type 'Fts5Context' skipped # Type 'Fts5PhraseIter' skipped # Type 'Fts5Context' skipped # Type 'Fts5PhraseIter' skipped # # ** 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: # ** # ** # ** # ** 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: # ** # **
  1. By mapping all synonyms to a single token. In this case, using # ** 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. # ** # **
  2. By querying the index for all synonyms of each query term # ** separately. 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: # ** # ** # ** ... MATCH 'first place' # ** # ** 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: # ** # ** # ** ... MATCH '(first OR 1st) place' # ** # ** 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. # ** # **
  3. 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 so would be # ** inefficient), it doesn't matter if the user queries for # ** 'first + place' or '1st + place', as there are entries in the # ** FTS index corresponding to both forms of the first token. # **
# ** # ** Whether it is parsing document or query text, any call to xToken that # ** specifies a tflags 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: # ** # ** # ** 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); # ** # ** # ** 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 substituted for "1st" by the tokenizer, then the query: # ** # ** # ** ... MATCH '1s*' # ** # ** 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. # Fts5Tokenizer* {.incompleteStruct.} = object fts5_tokenizer* {.incompleteStruct.} = object # Type 'fts5_tokenizer' skipped # Type 'Fts5Tokenizer' skipped # Type 'Fts5Tokenizer' skipped # Type 'Fts5Tokenizer' skipped # Type 'fts5_tokenizer' skipped # Type 'Fts5Tokenizer' skipped # Type 'Fts5Tokenizer' skipped # Type 'Fts5Tokenizer' skipped # # ** END OF CUSTOM TOKENIZERS # ************************************************************************ # ************************************************************************ # ** FTS5 EXTENSION REGISTRATION API # fts5_api* {.incompleteStruct.} = object # Type 'fts5_api' skipped # Type 'fts5_api' skipped # Type 'fts5_tokenizer' skipped # Type 'fts5_api' skipped # Type 'fts5_api' skipped # Type 'fts5_tokenizer' skipped # Type 'fts5_api' skipped # Type 'fts5_tokenizer' skipped # Type 'fts5_api' skipped # Type 'fts5_extension_function' skipped # # ** 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. # ** # **
# ** assert( sqlite3_libversion_number()==SQLITE_VERSION_NUMBER );
# ** assert( strncmp(sqlite3_sourceid(),SQLITE_SOURCE_ID,80)==0 );
# ** assert( strcmp(sqlite3_libversion(),SQLITE_VERSION)==0 );
# ** 
)^ # ** # ** ^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. Except if SQLite is built # ** using an edited copy of [the amalgamation], then the last four characters # ** of the hash might be different from [SQLITE_SOURCE_ID].)^ # ** # ** See also: [sqlite_version()] and [sqlite_source_id()]. # # Declaration 'sqlite3_version' skipped proc sqlite3_libversion*(): cstring {.impsqlite3C.} proc sqlite3_sourceid*(): cstring {.impsqlite3C.} proc sqlite3_libversion_number*(): cint {.impsqlite3C.} # # ** 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]. # proc sqlite3_compileoption_used*(zOptName: cstring): cint {.impsqlite3C.} proc sqlite3_compileoption_get*(N: cint): cstring {.impsqlite3C.} # # ** 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. # proc sqlite3_threadsafe*(): cint {.impsqlite3C.} # # ** 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. # # # ** If compiling for a processor that lacks floating point support, # ** substitute integer for floating-point. # # # ** 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. # ** # ** Ideally, 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 the database connection is associated with unfinalized prepared # ** statements, BLOB handlers, and/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, unclosed BLOB handlers, and/or unfinished sqlite3_backups, # ** it returns [SQLITE_OK] regardless, but instead of deallocating the database # ** connection immediately, it marks the database connection as an unusable # ** "zombie" and makes arrangements to automatically deallocate the database # ** connection after all prepared statements are finalized, all BLOB handles # ** are closed, and all backups have 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. # ** # ** ^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. # proc sqlite3_close*(a1: ptr sqlite3): cint {.impsqlite3C.} proc sqlite3_close_v2*(a1: ptr sqlite3): cint {.impsqlite3C.} # # ** 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: # ** # ** # # Declaration 'sqlite3_exec' skipped # Declaration 'sql' skipped # Declaration 'sqlite3_exec' skipped # Declaration 'sql' skipped # Declaration 'callback' skipped # Declaration 'errmsg' skipped # # ** 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. # proc sqlite3_initialize*(): cint {.impsqlite3C.} proc sqlite3_shutdown*(): cint {.impsqlite3C.} proc sqlite3_os_init*(): cint {.impsqlite3C.} proc sqlite3_os_end*(): cint {.impsqlite3C.} # # ** 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. # ** # ** 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. # ** # ** 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]. # proc sqlite3_config*(a1: cint): cint {.impsqlite3C.} # # ** 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. # proc sqlite3_db_config*(a1: ptr sqlite3, op: cint): cint {.impsqlite3C.} # # ** 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. # proc sqlite3_extended_result_codes*(a1: ptr sqlite3, onoff: cint): cint {.impsqlite3C.} # # ** 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 usually 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. # ** # ** As well as being set automatically as rows are inserted into database # ** tables, the value returned by this function may be set explicitly by # ** [sqlite3_set_last_insert_rowid()] # ** # ** Some virtual table implementations may INSERT rows into rowid tables as # ** part of committing a transaction (e.g. to flush data accumulated in memory # ** to disk). In this case subsequent calls to this function return the rowid # ** associated with these internal INSERT operations, which leads to # ** unintuitive results. Virtual table implementations that do write to rowid # ** tables in this way can avoid this problem by restoring the original # ** rowid value using [sqlite3_set_last_insert_rowid()] before returning # ** control to the user. # ** # ** ^(If an [INSERT] occurs within a trigger then this routine will # ** return the [rowid] of the inserted row as long as the trigger is # ** running. Once the trigger program ends, the value returned # ** by this routine reverts to what it was before the trigger was fired.)^ # ** # ** ^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]. # proc sqlite3_last_insert_rowid*(a1: ptr sqlite3): int64 {.impsqlite3C.} # # ** CAPI3REF: Set the Last Insert Rowid value. # ** METHOD: sqlite3 # ** # ** The sqlite3_set_last_insert_rowid(D, R) method allows the application to # ** set the value returned by calling sqlite3_last_insert_rowid(D) to R # ** without inserting a row into the database. # proc sqlite3_set_last_insert_rowid*(a1: ptr sqlite3, a2: int64) {.impsqlite3C.} # # ** 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: # ** # ** # ** # ** ^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. # ** # ** 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. # ** # ** See also: # ** # proc sqlite3_changes*(a1: ptr sqlite3): cint {.impsqlite3C.} # # ** 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. # ** # ** The [sqlite3_total_changes(D)] interface only reports the number # ** of rows that changed due to SQL statement run against database # ** connection D. Any changes by other database connections are ignored. # ** To detect changes against a database file from other database # ** connections use the [PRAGMA data_version] command or the # ** [SQLITE_FCNTL_DATA_VERSION] [file control]. # ** # ** 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. # ** # ** See also: # ** # proc sqlite3_total_changes*(a1: ptr sqlite3): cint {.impsqlite3C.} # # ** 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 statement count 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. # proc sqlite3_interrupt*(a1: ptr sqlite3) {.impsqlite3C.} # # ** 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. # proc sqlite3_complete*(sql: cstring): cint {.impsqlite3C.} proc sqlite3_complete16*(sql: pointer): cint {.impsqlite3C.} # # ** 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. # # Declaration 'sqlite3_busy_handler' skipped # Declaration 'sqlite3_busy_handler' skipped # # ** 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] # proc sqlite3_busy_timeout*(a1: ptr sqlite3, ms: cint): cint {.impsqlite3C.} # # ** 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 result table 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: # ** # **
# **        Name        | Age
# **        -----------------------
# **        Alice       | 43
# **        Bob         | 28
# **        Cindy       | 21
# ** 
# ** # ** There are two columns (M==2) and three rows (N==3). Thus the # ** result table has 8 entries. Suppose the result table is stored # ** in an array named azResult. Then azResult holds this content: # ** # **
# **        azResult[0] = "Name";
# **        azResult[1] = "Age";
# **        azResult[2] = "Alice";
# **        azResult[3] = "43";
# **        azResult[4] = "Bob";
# **        azResult[5] = "28";
# **        azResult[6] = "Cindy";
# **        azResult[7] = "21";
# ** 
)^ # ** # ** ^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()]. # # Declaration 'sqlite3_get_table' skipped # Declaration 'db' skipped # Declaration 'zSql' skipped # Declaration 'sqlite3_get_table' skipped # Declaration 'db' skipped # Declaration 'zSql' skipped # Declaration 'pazResult' skipped # Declaration 'pnRow' skipped # Declaration 'pnColumn' skipped # Declaration 'pzErrmsg' skipped proc sqlite3_free_table*(result: ptr cstring) {.impsqlite3C.} # # ** 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 formatting options from # ** the standard library printf() # ** plus some additional non-standard formats ([%q], [%Q], [%w], and [%z]). # ** See the [built-in printf()] documentation for details. # ** # ** ^The sqlite3_mprintf() and sqlite3_vmprintf() routines write their # ** results into memory obtained from [sqlite3_malloc64()]. # ** The strings returned by these two routines should be # ** released by [sqlite3_free()]. ^Both routines return a # ** NULL pointer if [sqlite3_malloc64()] 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(). # ** # ** See also: [built-in printf()], [printf() SQL function] # proc sqlite3_mprintf*(a1: cstring): cstring {.impsqlite3C.} proc sqlite3_snprintf*(a1: cint, a2: cstring, a3: cstring): cstring {.impsqlite3C.} # # ** 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. # ** # ** 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()]. # proc sqlite3_malloc*(a1: cint): pointer {.impsqlite3C.} proc sqlite3_malloc64*(a1: uint64): pointer {.impsqlite3C.} proc sqlite3_realloc*(a1: pointer, a2: cint): pointer {.impsqlite3C.} proc sqlite3_realloc64*(a1: pointer, a2: uint64): pointer {.impsqlite3C.} proc sqlite3_free*(a1: pointer) {.impsqlite3C.} proc sqlite3_msize*(a1: pointer): uint64 {.impsqlite3C.} # # ** 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. # proc sqlite3_memory_used*(): int64 {.impsqlite3C.} proc sqlite3_memory_highwater*(resetFlag: cint): int64 {.impsqlite3C.} # # ** 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 built-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. # proc sqlite3_randomness*(N: cint, P: pointer) {.impsqlite3C.} # # ** CAPI3REF: Compile-Time Authorization Callbacks # ** METHOD: sqlite3 # ** KEYWORDS: {authorizer callback} # ** # ** ^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_prepare_v3()], [sqlite3_prepare16()], [sqlite3_prepare16_v2()], # ** and [sqlite3_prepare16_v3()]. ^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 either NULL pointers or zero-terminated strings # ** that contain additional details about the action to be authorized. # ** Applications must always be prepared to encounter a NULL pointer in any # ** of the third through the sixth parameters of the authorization callback. # ** # ** ^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. # ** ^When a table is referenced by a [SELECT] but no column values are # ** extracted from that table (for example in a query like # ** "SELECT count(*) FROM tab") then the [SQLITE_READ] authorizer callback # ** is invoked once for that table with a column name that is an empty string. # ** ^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. # # Declaration 'sqlite3_set_authorizer' skipped # Declaration 'sqlite3_set_authorizer' skipped # Declaration 'xAuth' skipped # Declaration 'pUserData' skipped # # ** 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. Invoking # ** either [sqlite3_trace()] or [sqlite3_trace_v2()] will cancel the # ** profile callback. # # Declaration 'sqlite3_trace' skipped # Declaration 'sqlite3_trace' skipped # Declaration 'xTrace' skipped # Declaration 'sqlite3_profile' skipped # Declaration 'sqlite3_profile' skipped # Declaration 'xProfile' skipped # # ** 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. # # Declaration 'sqlite3_trace_v2' skipped # Declaration 'uMask' skipped # Declaration 'sqlite3_trace_v2' skipped # Declaration 'uMask' skipped # Declaration 'xCallback' skipped # Declaration 'pCtx' skipped # # ** 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. # ** # # Declaration 'sqlite3_progress_handler' skipped # Declaration 'sqlite3_progress_handler' skipped # # ** 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() must include, at a minimum, one of the following # ** three flag combinations:)^ # ** # **
# ** ^(
[SQLITE_OPEN_READONLY]
# **
The database is opened in read-only mode. If the database does not # ** already exist, an error is returned.
)^ # ** # ** ^(
[SQLITE_OPEN_READWRITE]
# **
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.
)^ # ** # ** ^(
[SQLITE_OPEN_READWRITE] | [SQLITE_OPEN_CREATE]
# **
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().
)^ # **
# ** # ** In addition to the required flags, the following optional flags are # ** also supported: # ** # **
# ** ^(
[SQLITE_OPEN_URI]
# **
The filename can be interpreted as a URI if this flag is set.
)^ # ** # ** ^(
[SQLITE_OPEN_MEMORY]
# **
The database will be opened as an in-memory database. The database # ** is named by the "filename" argument for the purposes of cache-sharing, # ** if shared cache mode is enabled, but the "filename" is otherwise ignored. # **
)^ # ** # ** ^(
[SQLITE_OPEN_NOMUTEX]
# **
The new database connection will use the "multi-thread" # ** [threading mode].)^ This means that separate threads are allowed # ** to use SQLite at the same time, as long as each thread is using # ** a different [database connection]. # ** # ** ^(
[SQLITE_OPEN_FULLMUTEX]
# **
The new database connection will use the "serialized" # ** [threading mode].)^ This means the multiple threads can safely # ** attempt to use the same database connection at the same time. # ** (Mutexes will block any actual concurrency, but in this mode # ** there is no harm in trying.) # ** # ** ^(
[SQLITE_OPEN_SHAREDCACHE]
# **
The database is opened [shared cache] enabled, overriding # ** the default shared cache setting provided by # ** [sqlite3_enable_shared_cache()].)^ # ** # ** ^(
[SQLITE_OPEN_PRIVATECACHE]
# **
The database is opened [shared cache] disabled, overriding # ** the default shared cache setting provided by # ** [sqlite3_enable_shared_cache()].)^ # ** # ** [[OPEN_NOFOLLOW]] ^(
[SQLITE_OPEN_NOFOLLOW]
# **
The database filename is not allowed to be a symbolic link
# **
)^ # ** # ** If the 3rd parameter to sqlite3_open_v2() is not one of the # ** required combinations shown above optionally combined with other # ** [SQLITE_OPEN_READONLY | SQLITE_OPEN_* bits] # ** then the behavior is undefined. # ** # ** ^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()]]

URI Filenames

# ** # ** ^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 third 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. # ** 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: # ** # ** # ** # ** ^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]]

URI filename examples

# ** # ** # **
URI filenames Results # **
file:data.db # ** Open the file "data.db" in the current directory. # **
file:/home/fred/data.db
# ** file:/home/fred/data.db
# ** file:localhost/home/fred/data.db
# ** Open the database file "/home/fred/data.db". # **
file:darkstar/home/fred/data.db # ** An error. "darkstar" is not a recognized authority. # **
# ** file:/C:/Documents%20and%20Settings/fred/Desktop/data.db # ** 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. # **
file:data.db?mode=ro&cache=private # ** 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. # **
file:/home/fred/data.db?vfs=unix-dotfile # ** Open file "/home/fred/data.db". Use the special VFS "unix-dotfile" # ** that uses dot-files in place of posix advisory locking. # **
file:data.db?mode=readonly # ** An error. "readonly" is not a valid option for the "mode" parameter. # **
# ** # ** ^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. # ** # ** Note to Windows users: 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(). # ** # ** Note to Windows Runtime users: 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] # proc sqlite3_open*(filename: cstring, ppDb: ptr ptr sqlite3): cint {.impsqlite3C.} proc sqlite3_open16*(filename: pointer, ppDb: ptr ptr sqlite3): cint {.impsqlite3C.} proc sqlite3_open_v2*(filename: cstring, ppDb: ptr ptr sqlite3, flags: cint, zVfs: cstring): cint {.impsqlite3C.} # # ** CAPI3REF: Obtain Values For URI Parameters # ** # ** These are utility routines, useful to [VFS|custom VFS implementations], # ** that check if a database file was a URI that contained a specific query # ** parameter, and if so obtains the value of that query parameter. # ** # ** The first parameter to these interfaces (hereafter referred to # ** as F) must be one of: # ** # ** If the F parameter is not one of the above, then the behavior is # ** undefined and probably undesirable. Older versions of SQLite were # ** more tolerant of invalid F parameters than newer versions. # ** # ** If F is a suitable filename (as described in the previous paragraph) # ** and if 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 and it # ** 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 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. # ** # ** The sqlite3_uri_key(F,N) returns a pointer to the name (not # ** the value) of the N-th query parameter for filename F, or a NULL # ** pointer if N is less than zero or greater than the number of query # ** parameters minus 1. The N value is zero-based so N should be 0 to obtain # ** the name of the first query parameter, 1 for the second parameter, and # ** so forth. # ** # ** 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 the SQLite core passed # ** into the xOpen VFS method, then the behavior of this routine is undefined # ** and probably undesirable. # ** # ** Beginning with SQLite [version 3.31.0] ([dateof:3.31.0]) the input F # ** parameter can also be the name of a rollback journal file or WAL file # ** in addition to the main database file. Prior to version 3.31.0, these # ** routines would only work if F was the name of the main database file. # ** When the F parameter is the name of the rollback journal or WAL file, # ** it has access to all the same query parameters as were found on the # ** main database file. # ** # ** See the [URI filename] documentation for additional information. # proc sqlite3_uri_parameter*(zFilename: cstring, zParam: cstring): cstring {.impsqlite3C.} proc sqlite3_uri_boolean*(zFile: cstring, zParam: cstring, bDefault: cint): cint {.impsqlite3C.} proc sqlite3_uri_int64*(a1: cstring, a2: cstring, a3: int64): int64 {.impsqlite3C.} proc sqlite3_uri_key*(zFilename: cstring, N: cint): cstring {.impsqlite3C.} # # ** CAPI3REF: Translate filenames # ** # ** These routines are available to [VFS|custom VFS implementations] for # ** translating filenames between the main database file, the journal file, # ** and the WAL file. # ** # ** If F is the name of an sqlite database file, journal file, or WAL file # ** passed by the SQLite core into the VFS, then sqlite3_filename_database(F) # ** returns the name of the corresponding database file. # ** # ** If F is the name of an sqlite database file, journal file, or WAL file # ** passed by the SQLite core into the VFS, or if F is a database filename # ** obtained from [sqlite3_db_filename()], then sqlite3_filename_journal(F) # ** returns the name of the corresponding rollback journal file. # ** # ** If F is the name of an sqlite database file, journal file, or WAL file # ** that was passed by the SQLite core into the VFS, or if F is a database # ** filename obtained from [sqlite3_db_filename()], then # ** sqlite3_filename_wal(F) returns the name of the corresponding # ** WAL file. # ** # ** In all of the above, if F is not the name of a database, journal or WAL # ** filename passed into the VFS from the SQLite core and F is not the # ** return value from [sqlite3_db_filename()], then the result is # ** undefined and is likely a memory access violation. # proc sqlite3_filename_database*(a1: cstring): cstring {.impsqlite3C.} proc sqlite3_filename_journal*(a1: cstring): cstring {.impsqlite3C.} proc sqlite3_filename_wal*(a1: cstring): cstring {.impsqlite3C.} # # ** CAPI3REF: Database File Corresponding To A Journal # ** # ** ^If X is the name of a rollback or WAL-mode journal file that is # ** passed into the xOpen method of [sqlite3_vfs], then # ** sqlite3_database_file_object(X) returns a pointer to the [sqlite3_file] # ** object that represents the main database file. # ** # ** This routine is intended for use in custom [VFS] implementations # ** only. It is not a general-purpose interface. # ** The argument sqlite3_file_object(X) must be a filename pointer that # ** has been passed into [sqlite3_vfs].xOpen method where the # ** flags parameter to xOpen contains one of the bits # ** [SQLITE_OPEN_MAIN_JOURNAL] or [SQLITE_OPEN_WAL]. Any other use # ** of this routine results in undefined and probably undesirable # ** behavior. # proc sqlite3_database_file_object*(a1: cstring): ptr sqlite3_file {.impsqlite3C.} # # ** CAPI3REF: Create and Destroy VFS Filenames # ** # ** These interfces are provided for use by [VFS shim] implementations and # ** are not useful outside of that context. # ** # ** The sqlite3_create_filename(D,J,W,N,P) allocates memory to hold a version of # ** database filename D with corresponding journal file J and WAL file W and # ** with N URI parameters key/values pairs in the array P. The result from # ** sqlite3_create_filename(D,J,W,N,P) is a pointer to a database filename that # ** is safe to pass to routines like: # ** # ** If a memory allocation error occurs, sqlite3_create_filename() might # ** return a NULL pointer. The memory obtained from sqlite3_create_filename(X) # ** must be released by a corresponding call to sqlite3_free_filename(Y). # ** # ** The P parameter in sqlite3_create_filename(D,J,W,N,P) should be an array # ** of 2*N pointers to strings. Each pair of pointers in this array corresponds # ** to a key and value for a query parameter. The P parameter may be a NULL # ** pointer if N is zero. None of the 2*N pointers in the P array may be # ** NULL pointers and key pointers should not be empty strings. # ** None of the D, J, or W parameters to sqlite3_create_filename(D,J,W,N,P) may # ** be NULL pointers, though they can be empty strings. # ** # ** The sqlite3_free_filename(Y) routine releases a memory allocation # ** previously obtained from sqlite3_create_filename(). Invoking # ** sqlite3_free_filename(Y) where Y is a NULL pointer is a harmless no-op. # ** # ** If the Y parameter to sqlite3_free_filename(Y) is anything other # ** than a NULL pointer or a pointer previously acquired from # ** sqlite3_create_filename(), then bad things such as heap # ** corruption or segfaults may occur. The value Y should be # ** used again after sqlite3_free_filename(Y) has been called. This means # ** that if the [sqlite3_vfs.xOpen()] method of a VFS has been called using Y, # ** then the corresponding [sqlite3_module.xClose() method should also be # ** invoked prior to calling sqlite3_free_filename(Y). # proc sqlite3_create_filename*(zDatabase: cstring, zJournal: cstring, zWal: cstring, nParam: cint, azParam: ptr cstring): cstring {.impsqlite3C.} proc sqlite3_free_filename*(a1: cstring) {.impsqlite3C.} # # ** 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. # ** ^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 values returned by sqlite3_errcode() and/or # ** sqlite3_extended_errcode() might change with each API call. # ** Except, there are some interfaces that are guaranteed to never # ** change the value of the error code. The error-code preserving # ** interfaces are: # ** # ** # ** # ** ^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. # proc sqlite3_errcode*(db: ptr sqlite3): cint {.impsqlite3C.} proc sqlite3_extended_errcode*(db: ptr sqlite3): cint {.impsqlite3C.} proc sqlite3_errmsg*(a1: ptr sqlite3): cstring {.impsqlite3C.} proc sqlite3_errmsg16*(a1: ptr sqlite3): pointer {.impsqlite3C.} proc sqlite3_errstr*(a1: cint): cstring {.impsqlite3C.} # # ** 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_NAME there is a # ** [limits | hard upper bound] # ** set at compile-time by a C preprocessor macro called # ** [limits | SQLITE_MAX_NAME]. # ** (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. # proc sqlite3_limit*(a1: ptr sqlite3, id: cint, newVal: cint): cint {.impsqlite3C.} # # ** CAPI3REF: Compiling An SQL Statement # ** KEYWORDS: {SQL statement compiler} # ** METHOD: sqlite3 # ** CONSTRUCTOR: sqlite3_stmt # ** # ** To execute an SQL statement, it must first be compiled into a byte-code # ** program using one of these routines. Or, in other words, these routines # ** are constructors for the [prepared statement] object. # ** # ** The preferred routine to use is [sqlite3_prepare_v2()]. The # ** [sqlite3_prepare()] interface is legacy and should be avoided. # ** [sqlite3_prepare_v3()] has an extra "prepFlags" option that is used # ** for special purposes. # ** # ** The use of the UTF-8 interfaces is preferred, as SQLite currently # ** does all parsing using UTF-8. The UTF-16 interfaces are provided # ** as a convenience. The UTF-16 interfaces work by converting the # ** input text into UTF-8, then invoking the corresponding UTF-8 interface. # ** # ** 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(), sqlite3_prepare_v2(), # ** and sqlite3_prepare_v3() # ** interfaces use UTF-8, and sqlite3_prepare16(), sqlite3_prepare16_v2(), # ** and sqlite3_prepare16_v3() 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 including # ** 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(), sqlite3_prepare_v3(), sqlite3_prepare16_v2(), # ** and sqlite3_prepare16_v3() interfaces are recommended for all new programs. # ** The older interfaces (sqlite3_prepare() and sqlite3_prepare16()) # ** are retained for backwards compatibility, but their use is discouraged. # ** ^In the "vX" 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: # ** # **
    # **
  1. # ** ^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. # **
  2. # ** # **
  3. # ** ^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. # **
  4. # ** # **
  5. # ** ^If the specific value bound to a [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 a 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_STAT4] compile-time option is enabled. # **
  6. # **
# ** # **

^sqlite3_prepare_v3() differs from sqlite3_prepare_v2() only in having # ** the extra prepFlags parameter, which is a bit array consisting of zero or # ** more of the [SQLITE_PREPARE_PERSISTENT|SQLITE_PREPARE_*] flags. ^The # ** sqlite3_prepare_v2() interface works exactly the same as # ** sqlite3_prepare_v3() with a zero prepFlags parameter. # proc sqlite3_prepare*(db: ptr sqlite3, zSql: cstring, nByte: cint, ppStmt: ptr ptr sqlite3_stmt, pzTail: ptr cstring): cint {.impsqlite3C.} proc sqlite3_prepare_v2*(db: ptr sqlite3, zSql: cstring, nByte: cint, ppStmt: ptr ptr sqlite3_stmt, pzTail: ptr cstring): cint {.impsqlite3C.} proc sqlite3_prepare_v3*(db: ptr sqlite3, zSql: cstring, nByte: cint, prepFlags: cuint, ppStmt: ptr ptr sqlite3_stmt, pzTail: ptr cstring): cint {.impsqlite3C.} proc sqlite3_prepare16*(db: ptr sqlite3, zSql: pointer, nByte: cint, ppStmt: ptr ptr sqlite3_stmt, pzTail: ptr pointer): cint {.impsqlite3C.} proc sqlite3_prepare16_v2*(db: ptr sqlite3, zSql: pointer, nByte: cint, ppStmt: ptr ptr sqlite3_stmt, pzTail: ptr pointer): cint {.impsqlite3C.} proc sqlite3_prepare16_v3*(db: ptr sqlite3, zSql: pointer, nByte: cint, prepFlags: cuint, ppStmt: ptr ptr sqlite3_stmt, pzTail: ptr pointer): cint {.impsqlite3C.} # # ** 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 [sqlite3_prepare_v2()], [sqlite3_prepare_v3()], # ** [sqlite3_prepare16_v2()], or [sqlite3_prepare16_v3()]. # ** ^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. # ** ^The sqlite3_normalized_sql(P) interface returns a pointer to a UTF-8 # ** string containing the normalized SQL text of prepared statement P. The # ** semantics used to normalize a SQL statement are unspecified and subject # ** to change. At a minimum, literal values will be replaced with suitable # ** placeholders. # ** # ** ^(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 strings returned by sqlite3_sql(P) and sqlite3_normalized_sql(P) # ** are managed by SQLite and are 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()]. # proc sqlite3_sql*(pStmt: ptr sqlite3_stmt): cstring {.impsqlite3C.} proc sqlite3_expanded_sql*(pStmt: ptr sqlite3_stmt): cstring {.impsqlite3C.} proc sqlite3_normalized_sql*(pStmt: ptr sqlite3_stmt): cstring {.impsqlite3C.} # # ** 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: # ** # **

# **    SELECT eval('DELETE FROM t1') FROM t2;
# ** 
# ** # ** 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. # ** ^The sqlite3_stmt_readonly() interface returns true for [BEGIN] since # ** [BEGIN] merely sets internal flags, but the [BEGIN|BEGIN IMMEDIATE] and # ** [BEGIN|BEGIN EXCLUSIVE] commands do touch the database and so # ** sqlite3_stmt_readonly() returns false for those commands. # proc sqlite3_stmt_readonly*(pStmt: ptr sqlite3_stmt): cint {.impsqlite3C.} # # ** CAPI3REF: Query The EXPLAIN Setting For A Prepared Statement # ** METHOD: sqlite3_stmt # ** # ** ^The sqlite3_stmt_isexplain(S) interface returns 1 if the # ** prepared statement S is an EXPLAIN statement, or 2 if the # ** statement S is an EXPLAIN QUERY PLAN. # ** ^The sqlite3_stmt_isexplain(S) interface returns 0 if S is # ** an ordinary statement or a NULL pointer. # proc sqlite3_stmt_isexplain*(pStmt: ptr sqlite3_stmt): cint {.impsqlite3C.} # # ** 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. # proc sqlite3_stmt_busy*(a1: ptr sqlite3_stmt): cint {.impsqlite3C.} # # ** 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: # ** # ** # ** # ** 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: 32766). # ** # ** ^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(). # ** ^If the third parameter to sqlite3_bind_text() is not NULL, then # ** it should be a pointer to well-formed UTF8 text. # ** ^If the third parameter to sqlite3_bind_text16() is not NULL, then # ** it should be a pointer to well-formed UTF16 text. # ** ^If the third parameter to sqlite3_bind_text64() is not NULL, then # ** it should be a pointer to a well-formed unicode string that is # ** either UTF8 if the sixth parameter is SQLITE_UTF8, or UTF16 # ** otherwise. # ** # ** [[byte-order determination rules]] ^The byte-order of # ** UTF16 input text is determined by the byte-order mark (BOM, U+FEFF) # ** found in first character, which is removed, or in the absence of a BOM # ** the byte order is the native byte order of the host # ** machine for sqlite3_bind_text16() or the byte order specified in # ** the 6th parameter for sqlite3_bind_text64().)^ # ** ^If UTF16 input text contains invalid unicode # ** characters, then SQLite might change those invalid characters # ** into the unicode replacement character: U+FFFD. # ** # ** ^(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 bytes 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 occurs 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 the bind API fails, # ** except the destructor is not called if the third parameter is a NULL # ** pointer or the fourth parameter is negative. # ** ^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. # ** # ** ^The sqlite3_bind_pointer(S,I,P,T,D) routine causes the I-th parameter in # ** [prepared statement] S to have an SQL value of NULL, but to also be # ** associated with the pointer P of type T. ^D is either a NULL pointer or # ** a pointer to a destructor function for P. ^SQLite will invoke the # ** destructor D with a single argument of P when it is finished using # ** P. The T parameter should be a static string, preferably a string # ** literal. The sqlite3_bind_pointer() routine is part of the # ** [pointer passing interface] added for SQLite 3.20.0. # ** # ** ^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()]. # # Declaration 'sqlite3_bind_blob' skipped # Declaration 'n' skipped # Declaration 'sqlite3_bind_blob' skipped # Declaration 'n' skipped # Declaration 'sqlite3_bind_blob64' skipped # Declaration 'sqlite3_bind_blob64' skipped proc sqlite3_bind_double*(a1: ptr sqlite3_stmt, a2: cint, a3: cdouble): cint {.impsqlite3C.} proc sqlite3_bind_int*(a1: ptr sqlite3_stmt, a2: cint, a3: cint): cint {.impsqlite3C.} proc sqlite3_bind_int64*(a1: ptr sqlite3_stmt, a2: cint, a3: int64): cint {.impsqlite3C.} proc sqlite3_bind_null*(a1: ptr sqlite3_stmt, a2: cint): cint {.impsqlite3C.} # Declaration 'sqlite3_bind_text' skipped # Declaration 'sqlite3_bind_text' skipped # Declaration 'sqlite3_bind_text16' skipped # Declaration 'sqlite3_bind_text16' skipped # Declaration 'sqlite3_bind_text64' skipped # Declaration 'sqlite3_bind_text64' skipped # Declaration 'encoding' skipped proc sqlite3_bind_value*(a1: ptr sqlite3_stmt, a2: cint, a3: ptr sqlite3_value): cint {.impsqlite3C.} # Declaration 'sqlite3_bind_pointer' skipped # Declaration 'sqlite3_bind_pointer' skipped proc sqlite3_bind_zeroblob*(a1: ptr sqlite3_stmt, a2: cint, n: cint): cint {.impsqlite3C.} proc sqlite3_bind_zeroblob64*(a1: ptr sqlite3_stmt, a2: cint, a3: uint64): cint {.impsqlite3C.} # # ** 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", "$AAA", or "@AAA" that serve as # ** placeholders for values that are [sqlite3_bind_blob | bound] # ** to the parameters at a later time. # ** # ** ^(This routine actually returns the index of the largest (rightmost) # ** parameter. For all forms except ?NNN, this will correspond to the # ** number of unique parameters. If parameters of the ?NNN form are used, # ** there may be gaps in the list.)^ # ** # ** See also: [sqlite3_bind_blob|sqlite3_bind()], # ** [sqlite3_bind_parameter_name()], and # ** [sqlite3_bind_parameter_index()]. # proc sqlite3_bind_parameter_count*(a1: ptr sqlite3_stmt): cint {.impsqlite3C.} # # ** CAPI3REF: Name Of A Host Parameter # ** METHOD: sqlite3_stmt # ** # ** ^The sqlite3_bind_parameter_name(P,N) interface returns # ** the name of the N-th [SQL parameter] in the [prepared statement] P. # ** ^(SQL parameters of the form "?NNN" or ":AAA" or "@AAA" or "$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()], # ** [sqlite3_prepare16_v2()], or [sqlite3_prepare16_v3()]. # ** # ** See also: [sqlite3_bind_blob|sqlite3_bind()], # ** [sqlite3_bind_parameter_count()], and # ** [sqlite3_bind_parameter_index()]. # proc sqlite3_bind_parameter_name*(a1: ptr sqlite3_stmt, a2: cint): cstring {.impsqlite3C.} # # ** 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()] or # ** [sqlite3_prepare16_v3()]. # ** # ** See also: [sqlite3_bind_blob|sqlite3_bind()], # ** [sqlite3_bind_parameter_count()], and # ** [sqlite3_bind_parameter_name()]. # proc sqlite3_bind_parameter_index*(a1: ptr sqlite3_stmt, zName: cstring): cint {.impsqlite3C.} # # ** 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. # proc sqlite3_clear_bindings*(a1: ptr sqlite3_stmt): cint {.impsqlite3C.} # # ** 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]. ^If this routine returns 0, that means the # ** [prepared statement] returns no data (for example an [UPDATE]). # ** ^However, just because this routine returns a positive number does not # ** mean that one or more rows of data will be returned. ^A SELECT statement # ** will always have a positive sqlite3_column_count() but depending on the # ** WHERE clause constraints and the table content, it might return no rows. # ** # ** See also: [sqlite3_data_count()] # proc sqlite3_column_count*(pStmt: ptr sqlite3_stmt): cint {.impsqlite3C.} # # ** 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. # proc sqlite3_column_name*(a1: ptr sqlite3_stmt, N: cint): cstring {.impsqlite3C.} proc sqlite3_column_name16*(a1: ptr sqlite3_stmt, N: cint): pointer {.impsqlite3C.} # # ** 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 routines 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 # ** [sqlite3_column_database_name | column metadata interfaces] # ** for the same [prepared statement] and result column # ** at the same time then the results are undefined. # proc sqlite3_column_database_name*(a1: ptr sqlite3_stmt, a2: cint): cstring {.impsqlite3C.} proc sqlite3_column_database_name16*(a1: ptr sqlite3_stmt, a2: cint): pointer {.impsqlite3C.} proc sqlite3_column_table_name*(a1: ptr sqlite3_stmt, a2: cint): cstring {.impsqlite3C.} proc sqlite3_column_table_name16*(a1: ptr sqlite3_stmt, a2: cint): pointer {.impsqlite3C.} proc sqlite3_column_origin_name*(a1: ptr sqlite3_stmt, a2: cint): cstring {.impsqlite3C.} proc sqlite3_column_origin_name16*(a1: ptr sqlite3_stmt, a2: cint): pointer {.impsqlite3C.} # # ** 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. # proc sqlite3_column_decltype*(a1: ptr sqlite3_stmt, a2: cint): cstring {.impsqlite3C.} proc sqlite3_column_decltype16*(a1: ptr sqlite3_stmt, a2: cint): pointer {.impsqlite3C.} # # ** CAPI3REF: Evaluate An SQL Statement # ** METHOD: sqlite3_stmt # ** # ** After a [prepared statement] has been prepared using any of # ** [sqlite3_prepare_v2()], [sqlite3_prepare_v3()], [sqlite3_prepare16_v2()], # ** or [sqlite3_prepare16_v3()] 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 "vX" interfaces # ** [sqlite3_prepare_v3()], [sqlite3_prepare_v2()], [sqlite3_prepare16_v3()], # ** [sqlite3_prepare16_v2()] or the older legacy # ** interfaces [sqlite3_prepare()] and [sqlite3_prepare16()]. The use of the # ** new "vX" 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. # ** # ** Goofy Interface Alert: 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 [sqlite3_prepare_v3()] or [sqlite3_prepare_v2()] # ** or [sqlite3_prepare16_v2()] or [sqlite3_prepare16_v3()] 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 "vX" interfaces is recommended. # proc sqlite3_step*(a1: ptr sqlite3_stmt): cint {.impsqlite3C.} # # ** 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()] family 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()] # proc sqlite3_data_count*(pStmt: ptr sqlite3_stmt): cint {.impsqlite3C.} # # ** CAPI3REF: Result Values From A Query # ** KEYWORDS: {column access functions} # ** METHOD: sqlite3_stmt # ** # ** Summary: # **
# **
sqlite3_column_blobBLOB result # **
sqlite3_column_doubleREAL result # **
sqlite3_column_int32-bit INTEGER result # **
sqlite3_column_int6464-bit INTEGER result # **
sqlite3_column_textUTF-8 TEXT result # **
sqlite3_column_text16UTF-16 TEXT result # **
sqlite3_column_valueThe result as an # ** [sqlite3_value|unprotected sqlite3_value] object. # **
    # **
sqlite3_column_bytesSize of a BLOB # ** or a UTF-8 TEXT result in bytes # **
sqlite3_column_bytes16   # ** →  Size of UTF-16 # ** TEXT in bytes # **
sqlite3_column_typeDefault # ** datatype of the result # **
# ** # ** Details: # ** # ** ^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 first six interfaces (_blob, _double, _int, _int64, _text, and _text16) # ** each return the value of a result column in a specific data format. If # ** the result column is not initially in the requested format (for example, # ** if the query returns an integer but the sqlite3_column_text() interface # ** is used to extract the value) then an automatic type conversion is performed. # ** # ** ^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 return value of sqlite3_column_type() can be used to decide which # ** of the first six interface should be used to extract the column value. # ** The value returned by sqlite3_column_type() is only meaningful if no # ** automatic type conversions have occurred for the value in question. # ** After a type conversion, the result of calling sqlite3_column_type() # ** is undefined, though harmless. Future # ** versions of SQLite may change the behavior of sqlite3_column_type() # ** following a type conversion. # ** # ** If the result is a BLOB or a TEXT string, then the sqlite3_column_bytes() # ** or sqlite3_column_bytes16() interfaces can be used to determine the size # ** of that BLOB or string. # ** # ** ^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. # ** # ** Warning: ^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. # ** Hence, the sqlite3_column_value() interface # ** is normally only useful within the implementation of # ** [application-defined SQL functions] or [virtual tables], not within # ** top-level application code. # ** # ** The these routines may attempt to convert the datatype of the result. # ** ^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: # ** # **
# ** # **
Internal
Type
Requested
Type
Conversion # ** # **
NULL INTEGER Result is 0 # **
NULL FLOAT Result is 0.0 # **
NULL TEXT Result is a NULL pointer # **
NULL BLOB Result is a NULL pointer # **
INTEGER FLOAT Convert from integer to float # **
INTEGER TEXT ASCII rendering of the integer # **
INTEGER BLOB Same as INTEGER->TEXT # **
FLOAT INTEGER [CAST] to INTEGER # **
FLOAT TEXT ASCII rendering of the float # **
FLOAT BLOB [CAST] to BLOB # **
TEXT INTEGER [CAST] to INTEGER # **
TEXT FLOAT [CAST] to REAL # **
TEXT BLOB No change # **
BLOB INTEGER [CAST] to INTEGER # **
BLOB FLOAT [CAST] to REAL # **
BLOB TEXT Add a zero terminator if needed # **
# **
)^ # ** # ** 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: # ** # ** # ** # ** ^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: # ** # ** # ** # ** 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 not pass the pointers returned # ** from [sqlite3_column_blob()], [sqlite3_column_text()], etc. into # ** [sqlite3_free()]. # ** # ** As long as the input parameters are correct, these routines will only # ** fail if an out-of-memory error occurs during a format conversion. # ** Only the following subset of interfaces are subject to out-of-memory # ** errors: # ** # ** # ** # ** If an out-of-memory error occurs, then the return value from these # ** routines is the same as if the column had contained an SQL NULL value. # ** Valid SQL NULL returns can be distinguished from out-of-memory errors # ** by invoking the [sqlite3_errcode()] immediately after the suspect # ** return value is obtained and before any # ** other SQLite interface is called on the same [database connection]. # proc sqlite3_column_blob*(a1: ptr sqlite3_stmt, iCol: cint): pointer {.impsqlite3C.} proc sqlite3_column_double*(a1: ptr sqlite3_stmt, iCol: cint): cdouble {.impsqlite3C.} proc sqlite3_column_int*(a1: ptr sqlite3_stmt, iCol: cint): cint {.impsqlite3C.} proc sqlite3_column_int64*(a1: ptr sqlite3_stmt, iCol: cint): int64 {.impsqlite3C.} proc sqlite3_column_text*(a1: ptr sqlite3_stmt, iCol: cint): ptr cuchar {.impsqlite3C.} proc sqlite3_column_text16*(a1: ptr sqlite3_stmt, iCol: cint): pointer {.impsqlite3C.} proc sqlite3_column_value*(a1: ptr sqlite3_stmt, iCol: cint): ptr sqlite3_value {.impsqlite3C.} proc sqlite3_column_bytes*(a1: ptr sqlite3_stmt, iCol: cint): cint {.impsqlite3C.} proc sqlite3_column_bytes16*(a1: ptr sqlite3_stmt, iCol: cint): cint {.impsqlite3C.} proc sqlite3_column_type*(a1: ptr sqlite3_stmt, iCol: cint): cint {.impsqlite3C.} # # ** 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. # proc sqlite3_finalize*(pStmt: ptr sqlite3_stmt): cint {.impsqlite3C.} # # ** 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. # proc sqlite3_reset*(pStmt: ptr sqlite3_stmt): cint {.impsqlite3C.} # # ** CAPI3REF: Create Or Redefine SQL Functions # ** KEYWORDS: {function creation routines} # ** 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 # ** the three "sqlite3_create_function*" 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. Function sqlite3_create_window_function() # ** is similar, but allows the user to supply the extra callback functions # ** needed by [aggregate window functions]. # ** # ** ^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 fourth parameter may also optionally include the [SQLITE_DIRECTONLY] # ** flag, which if present prevents the function from being invoked from # ** within VIEWs, TRIGGERs, CHECK constraints, generated column expressions, # ** index expressions, or the WHERE clause of partial indexes. # ** # ** # ** For best security, the [SQLITE_DIRECTONLY] flag is recommended for # ** all application-defined SQL functions that do not need to be # ** used inside of triggers, view, CHECK constraints, or other elements of # ** the database schema. This flags is especially recommended for SQL # ** functions that have side effects or reveal internal application state. # ** Without this flag, an attacker might be able to modify the schema of # ** a database file to include invocations of the function with parameters # ** chosen by the attacker, which the application will then execute when # ** the database file is opened and read. # ** # ** # ** ^(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 passed to the three # ** "sqlite3_create_function*" functions, 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. # ** # ** ^The sixth, seventh, eighth and ninth parameters (xStep, xFinal, xValue # ** and xInverse) passed to sqlite3_create_window_function are pointers to # ** C-language callbacks that implement the new function. xStep and xFinal # ** must both be non-NULL. xValue and xInverse may either both be NULL, in # ** which case a regular aggregate function is created, or must both be # ** non-NULL, in which case the new function may be used as either an aggregate # ** or aggregate window function. More details regarding the implementation # ** of aggregate window functions are # ** [user-defined window functions|available here]. # ** # ** ^(If the final parameter to sqlite3_create_function_v2() or # ** sqlite3_create_window_function() 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 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. # # Declaration 'sqlite3_create_function' skipped # Declaration 'db' skipped # Declaration 'zFunctionName' skipped # Declaration 'nArg' skipped # Declaration 'eTextRep' skipped # Declaration 'pApp' skipped # Declaration 'sqlite3_create_function' skipped # Declaration 'db' skipped # Declaration 'zFunctionName' skipped # Declaration 'nArg' skipped # Declaration 'eTextRep' skipped # Declaration 'pApp' skipped # Declaration 'xFunc' skipped # Declaration 'xStep' skipped # Declaration 'xFinal' skipped # Declaration 'sqlite3_create_function16' skipped # Declaration 'db' skipped # Declaration 'zFunctionName' skipped # Declaration 'nArg' skipped # Declaration 'eTextRep' skipped # Declaration 'pApp' skipped # Declaration 'sqlite3_create_function16' skipped # Declaration 'db' skipped # Declaration 'zFunctionName' skipped # Declaration 'nArg' skipped # Declaration 'eTextRep' skipped # Declaration 'pApp' skipped # Declaration 'xFunc' skipped # Declaration 'xStep' skipped # Declaration 'xFinal' skipped # Declaration 'sqlite3_create_function_v2' skipped # Declaration 'db' skipped # Declaration 'zFunctionName' skipped # Declaration 'nArg' skipped # Declaration 'eTextRep' skipped # Declaration 'pApp' skipped # Declaration 'sqlite3_create_function_v2' skipped # Declaration 'db' skipped # Declaration 'zFunctionName' skipped # Declaration 'nArg' skipped # Declaration 'eTextRep' skipped # Declaration 'pApp' skipped # Declaration 'xFunc' skipped # Declaration 'xStep' skipped # Declaration 'xFinal' skipped # Declaration 'xDestroy' skipped # Declaration 'sqlite3_create_window_function' skipped # Declaration 'db' skipped # Declaration 'zFunctionName' skipped # Declaration 'nArg' skipped # Declaration 'eTextRep' skipped # Declaration 'pApp' skipped # Declaration 'sqlite3_create_window_function' skipped # Declaration 'db' skipped # Declaration 'zFunctionName' skipped # Declaration 'nArg' skipped # Declaration 'eTextRep' skipped # Declaration 'pApp' skipped # Declaration 'xStep' skipped # Declaration 'xFinal' skipped # Declaration 'xValue' skipped # Declaration 'xInverse' skipped # Declaration 'xDestroy' skipped # # ** 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. # proc sqlite3_aggregate_count*(a1: ptr sqlite3_context): cint {.impsqlite3C.} proc sqlite3_expired*(a1: ptr sqlite3_stmt): cint {.impsqlite3C.} proc sqlite3_transfer_bindings*(a1: ptr sqlite3_stmt, a2: ptr sqlite3_stmt): cint {.impsqlite3C.} proc sqlite3_global_recover*(): cint {.impsqlite3C.} proc sqlite3_thread_cleanup*() {.impsqlite3C.} # Declaration 'sqlite3_memory_alarm' skipped # Declaration 'sqlite3_memory_alarm' skipped # # ** CAPI3REF: Obtaining SQL Values # ** METHOD: sqlite3_value # ** # ** Summary: # **
# **
sqlite3_value_blobBLOB value # **
sqlite3_value_doubleREAL value # **
sqlite3_value_int32-bit INTEGER value # **
sqlite3_value_int6464-bit INTEGER value # **
sqlite3_value_pointerPointer value # **
sqlite3_value_textUTF-8 TEXT value # **
sqlite3_value_text16UTF-16 TEXT value in # ** the native byteorder # **
sqlite3_value_text16beUTF-16be TEXT value # **
sqlite3_value_text16leUTF-16le TEXT value # **
    # **
sqlite3_value_bytesSize of a BLOB # ** or a UTF-8 TEXT in bytes # **
sqlite3_value_bytes16   # ** →  Size of UTF-16 # ** TEXT in bytes # **
sqlite3_value_typeDefault # ** datatype of the value # **
sqlite3_value_numeric_type   # ** →  Best numeric datatype of the value # **
sqlite3_value_nochange   # ** →  True if the column is unchanged in an UPDATE # ** against a virtual table. # **
sqlite3_value_frombind   # ** →  True if value originated from a [bound parameter] # **
# ** # ** Details: # ** # ** These routines extract type, size, and content information from # ** [protected sqlite3_value] objects. Protected sqlite3_value objects # ** are used to pass parameter information into the functions that # ** implement [application-defined SQL functions] and [virtual tables]. # ** # ** These routines work only with [protected sqlite3_value] objects. # ** Any attempt to use these routines on an [unprotected sqlite3_value] # ** is not threadsafe. # ** # ** ^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. # ** # ** ^If [sqlite3_value] object V was initialized # ** using [sqlite3_bind_pointer(S,I,P,X,D)] or [sqlite3_result_pointer(C,P,X,D)] # ** and if X and Y are strings that compare equal according to strcmp(X,Y), # ** then sqlite3_value_pointer(V,Y) will return the pointer P. ^Otherwise, # ** sqlite3_value_pointer(V,Y) returns a NULL. The sqlite3_bind_pointer() # ** routine is part of the [pointer passing interface] added for SQLite 3.20.0. # ** # ** ^(The sqlite3_value_type(V) interface returns the # ** [SQLITE_INTEGER | datatype code] for the initial datatype of the # ** [sqlite3_value] object V. The returned value is one of [SQLITE_INTEGER], # ** [SQLITE_FLOAT], [SQLITE_TEXT], [SQLITE_BLOB], or [SQLITE_NULL].)^ # ** Other interfaces might change the datatype for an sqlite3_value object. # ** For example, if the datatype is initially SQLITE_INTEGER and # ** sqlite3_value_text(V) is called to extract a text value for that # ** integer, then subsequent calls to sqlite3_value_type(V) might return # ** SQLITE_TEXT. Whether or not a persistent internal datatype conversion # ** occurs is undefined and may change from one release of SQLite to the next. # ** # ** ^(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.)^ # ** # ** ^Within the [xUpdate] method of a [virtual table], the # ** sqlite3_value_nochange(X) interface returns true if and only if # ** the column corresponding to X is unchanged by the UPDATE operation # ** that the xUpdate method call was invoked to implement and if # ** and the prior [xColumn] method call that was invoked to extracted # ** the value for that column returned without setting a result (probably # ** because it queried [sqlite3_vtab_nochange()] and found that the column # ** was unchanging). ^Within an [xUpdate] method, any value for which # ** sqlite3_value_nochange(X) is true will in all other respects appear # ** to be a NULL value. If sqlite3_value_nochange(X) is invoked anywhere other # ** than within an [xUpdate] method call for an UPDATE statement, then # ** the return value is arbitrary and meaningless. # ** # ** ^The sqlite3_value_frombind(X) interface returns non-zero if the # ** value X originated from one of the [sqlite3_bind_int|sqlite3_bind()] # ** interfaces. ^If X comes from an SQL literal value, or a table column, # ** or an expression, then sqlite3_value_frombind(X) returns zero. # ** # ** 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. # ** # ** As long as the input parameter is correct, these routines can only # ** fail if an out-of-memory error occurs during a format conversion. # ** Only the following subset of interfaces are subject to out-of-memory # ** errors: # ** # ** # ** # ** If an out-of-memory error occurs, then the return value from these # ** routines is the same as if the column had contained an SQL NULL value. # ** Valid SQL NULL returns can be distinguished from out-of-memory errors # ** by invoking the [sqlite3_errcode()] immediately after the suspect # ** return value is obtained and before any # ** other SQLite interface is called on the same [database connection]. # proc sqlite3_value_blob*(a1: ptr sqlite3_value): pointer {.impsqlite3C.} proc sqlite3_value_double*(a1: ptr sqlite3_value): cdouble {.impsqlite3C.} proc sqlite3_value_int*(a1: ptr sqlite3_value): cint {.impsqlite3C.} proc sqlite3_value_int64*(a1: ptr sqlite3_value): int64 {.impsqlite3C.} proc sqlite3_value_pointer*(a1: ptr sqlite3_value, a2: cstring): pointer {.impsqlite3C.} proc sqlite3_value_text*(a1: ptr sqlite3_value): ptr cuchar {.impsqlite3C.} proc sqlite3_value_text16*(a1: ptr sqlite3_value): pointer {.impsqlite3C.} proc sqlite3_value_text16le*(a1: ptr sqlite3_value): pointer {.impsqlite3C.} proc sqlite3_value_text16be*(a1: ptr sqlite3_value): pointer {.impsqlite3C.} proc sqlite3_value_bytes*(a1: ptr sqlite3_value): cint {.impsqlite3C.} proc sqlite3_value_bytes16*(a1: ptr sqlite3_value): cint {.impsqlite3C.} proc sqlite3_value_type*(a1: ptr sqlite3_value): cint {.impsqlite3C.} proc sqlite3_value_numeric_type*(a1: ptr sqlite3_value): cint {.impsqlite3C.} proc sqlite3_value_nochange*(a1: ptr sqlite3_value): cint {.impsqlite3C.} proc sqlite3_value_frombind*(a1: ptr sqlite3_value): cint {.impsqlite3C.} # # ** 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. # proc sqlite3_value_subtype*(a1: ptr sqlite3_value): cuint {.impsqlite3C.} # # ** 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. # proc sqlite3_value_dup*(a1: ptr sqlite3_value): ptr sqlite3_value {.impsqlite3C.} proc sqlite3_value_free*(a1: ptr sqlite3_value) {.impsqlite3C.} # # ** 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 bytes 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 any 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. # proc sqlite3_aggregate_context*(a1: ptr sqlite3_context, nBytes: cint): pointer {.impsqlite3C.} # # ** 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. # proc sqlite3_user_data*(a1: ptr sqlite3_context): pointer {.impsqlite3C.} # # ** 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. # proc sqlite3_context_db_handle*(a1: ptr sqlite3_context): ptr sqlite3 {.impsqlite3C.} # # ** 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(C,N) interface returns a pointer to the metadata # ** associated by the sqlite3_set_auxdata(C,N,P,X) function with the Nth argument # ** value to the application-defined function. ^N is zero for the left-most # ** function argument. ^If there is no metadata # ** associated with the function argument, the sqlite3_get_auxdata(C,N) 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: # ** # ** 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.)^ # ** # ** The value of the N parameter to these interfaces should be non-negative. # ** Future enhancements may make use of negative N values to define new # ** kinds of function caching behavior. # ** # ** These routines must be called from the same thread in which # ** the SQL function is running. # proc sqlite3_get_auxdata*(a1: ptr sqlite3_context, N: cint): pointer {.impsqlite3C.} # Declaration 'sqlite3_set_auxdata' skipped # Declaration 'N' skipped # Declaration 'sqlite3_set_auxdata' skipped # Declaration 'N' skipped # # ** 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 using # ** the same [byte-order determination rules] as [sqlite3_bind_text16()]. # ** ^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 [sqlite3_malloc()] before it returns. # ** # ** ^For the sqlite3_result_text16(), sqlite3_result_text16le(), and # ** sqlite3_result_text16be() routines, and for sqlite3_result_text64() # ** when the encoding is not UTF8, if the input UTF16 begins with a # ** byte-order mark (BOM, U+FEFF) then the BOM is removed from the # ** string and the rest of the string is interpreted according to the # ** byte-order specified by the BOM. ^The byte-order specified by # ** the BOM at the beginning of the text overrides the byte-order # ** specified by the interface procedure. ^So, for example, if # ** sqlite3_result_text16le() is invoked with text that begins # ** with bytes 0xfe, 0xff (a big-endian byte-order mark) then the # ** first two bytes of input are skipped and the remaining input # ** is interpreted as UTF16BE text. # ** # ** ^For UTF16 input text to the sqlite3_result_text16(), # ** sqlite3_result_text16be(), sqlite3_result_text16le(), and # ** sqlite3_result_text64() routines, if the text contains invalid # ** UTF16 characters, the invalid characters might be converted # ** into the unicode replacement character, U+FFFD. # ** # ** ^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. # ** # ** ^The sqlite3_result_pointer(C,P,T,D) interface sets the result to an # ** SQL NULL value, just like [sqlite3_result_null(C)], except that it # ** also associates the host-language pointer P or type T with that # ** NULL value such that the pointer can be retrieved within an # ** [application-defined SQL function] using [sqlite3_value_pointer()]. # ** ^If the D parameter is not NULL, then it is a pointer to a destructor # ** for the P parameter. ^SQLite invokes D with P as its only argument # ** when SQLite is finished with P. The T parameter should be a static # ** string and preferably a string literal. The sqlite3_result_pointer() # ** routine is part of the [pointer passing interface] added for SQLite 3.20.0. # ** # ** 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. # # Declaration 'sqlite3_result_blob' skipped # Declaration 'sqlite3_result_blob' skipped # Declaration 'sqlite3_result_blob64' skipped # Declaration 'sqlite3_result_blob64' skipped proc sqlite3_result_double*(a1: ptr sqlite3_context, a2: cdouble) {.impsqlite3C.} proc sqlite3_result_error*(a1: ptr sqlite3_context, a2: cstring, a3: cint) {.impsqlite3C.} proc sqlite3_result_error16*(a1: ptr sqlite3_context, a2: pointer, a3: cint) {.impsqlite3C.} proc sqlite3_result_error_toobig*(a1: ptr sqlite3_context) {.impsqlite3C.} proc sqlite3_result_error_nomem*(a1: ptr sqlite3_context) {.impsqlite3C.} proc sqlite3_result_error_code*(a1: ptr sqlite3_context, a2: cint) {.impsqlite3C.} proc sqlite3_result_int*(a1: ptr sqlite3_context, a2: cint) {.impsqlite3C.} proc sqlite3_result_int64*(a1: ptr sqlite3_context, a2: int64) {.impsqlite3C.} proc sqlite3_result_null*(a1: ptr sqlite3_context) {.impsqlite3C.} # Declaration 'sqlite3_result_text' skipped # Declaration 'sqlite3_result_text' skipped # Declaration 'sqlite3_result_text64' skipped # Declaration 'sqlite3_result_text64' skipped # Declaration 'encoding' skipped # Declaration 'sqlite3_result_text16' skipped # Declaration 'sqlite3_result_text16' skipped # Declaration 'sqlite3_result_text16le' skipped # Declaration 'sqlite3_result_text16le' skipped # Declaration 'sqlite3_result_text16be' skipped # Declaration 'sqlite3_result_text16be' skipped proc sqlite3_result_value*(a1: ptr sqlite3_context, a2: ptr sqlite3_value) {.impsqlite3C.} # Declaration 'sqlite3_result_pointer' skipped # Declaration 'sqlite3_result_pointer' skipped proc sqlite3_result_zeroblob*(a1: ptr sqlite3_context, n: cint) {.impsqlite3C.} proc sqlite3_result_zeroblob64*(a1: ptr sqlite3_context, n: uint64): cint {.impsqlite3C.} # # ** 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. # proc sqlite3_result_subtype*(a1: ptr sqlite3_context, a2: cuint) {.impsqlite3C.} # # ** 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: # ** )^ # ** ^The eTextRep argument determines the encoding of strings passed # ** to the collating function callback, xCompare. # ** ^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, xCompare, 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 xCompare 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 two integer parameters to the collating # ** function callback are the length of the two strings, in bytes. 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: # ** # **
    # **
  1. If A==B then B==A. # **
  2. If A==B and B==C then A==C. # **
  3. If A<B THEN B>A. # **
  4. If A<B and B<C then A<C. # **
# ** # ** 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 not 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()]. # # Declaration 'sqlite3_create_collation' skipped # Declaration 'zName' skipped # Declaration 'eTextRep' skipped # Declaration 'pArg' skipped # Declaration 'sqlite3_create_collation' skipped # Declaration 'zName' skipped # Declaration 'eTextRep' skipped # Declaration 'pArg' skipped # Declaration 'xCompare' skipped # Declaration 'sqlite3_create_collation_v2' skipped # Declaration 'zName' skipped # Declaration 'eTextRep' skipped # Declaration 'pArg' skipped # Declaration 'sqlite3_create_collation_v2' skipped # Declaration 'zName' skipped # Declaration 'eTextRep' skipped # Declaration 'pArg' skipped # Declaration 'xCompare' skipped # Declaration 'xDestroy' skipped # Declaration 'sqlite3_create_collation16' skipped # Declaration 'zName' skipped # Declaration 'eTextRep' skipped # Declaration 'pArg' skipped # Declaration 'sqlite3_create_collation16' skipped # Declaration 'zName' skipped # Declaration 'eTextRep' skipped # Declaration 'pArg' skipped # Declaration 'xCompare' skipped # # ** 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()]. # # Declaration 'sqlite3_collation_needed' skipped # Declaration 'sqlite3_collation_needed' skipped # Declaration 'eTextRep' skipped # Declaration 'sqlite3_collation_needed16' skipped # Declaration 'sqlite3_collation_needed16' skipped # Declaration 'eTextRep' skipped # # ** 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. # proc sqlite3_sleep*(a1: cint): cint {.impsqlite3C.} # # ** 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. # ** # ** Note to Windows Runtime users: 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: # ** # **
# ** 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);
# ** 
# # Declaration 'sqlite3_temp_directory' skipped # # ** 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. # # Declaration 'sqlite3_data_directory' skipped # # ** CAPI3REF: Win32 Specific Interface # ** # ** These interfaces are available only on Windows. The # ** [sqlite3_win32_set_directory] interface is used to set the value associated # ** with the [sqlite3_temp_directory] or [sqlite3_data_directory] variable, to # ** zValue, depending on the value of the type parameter. The zValue parameter # ** should be NULL to cause the previous value to be freed via [sqlite3_free]; # ** a non-NULL value will be copied into memory obtained from [sqlite3_malloc] # ** prior to being used. The [sqlite3_win32_set_directory] interface returns # ** [SQLITE_OK] to indicate success, [SQLITE_ERROR] if the type is unsupported, # ** or [SQLITE_NOMEM] if memory could not be allocated. The value of the # ** [sqlite3_data_directory] variable is intended to act as a replacement for # ** the current directory on the sub-platforms of Win32 where that concept is # ** not present, e.g. WinRT and UWP. The [sqlite3_win32_set_directory8] and # ** [sqlite3_win32_set_directory16] interfaces behave exactly the same as the # ** sqlite3_win32_set_directory interface except the string parameter must be # ** UTF-8 or UTF-16, respectively. # proc sqlite3_win32_set_directory*(`type`: culong, zValue: pointer): cint {.impsqlite3C.} proc sqlite3_win32_set_directory8*(`type`: culong, zValue: cstring): cint {.impsqlite3C.} proc sqlite3_win32_set_directory16*(`type`: culong, zValue: pointer): cint {.impsqlite3C.} # # ** 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. # proc sqlite3_get_autocommit*(a1: ptr sqlite3): cint {.impsqlite3C.} # # ** 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. # proc sqlite3_db_handle*(a1: ptr sqlite3_stmt): ptr sqlite3 {.impsqlite3C.} # # ** CAPI3REF: Return The Filename For A Database Connection # ** METHOD: sqlite3 # ** # ** ^The sqlite3_db_filename(D,N) interface returns a pointer to the filename # ** associated with database N of connection D. # ** ^If there is no attached database N on the database # ** connection D, or if database N is a temporary or in-memory database, then # ** this function will return either a NULL pointer or an empty string. # ** # ** ^The string value returned by this routine is owned and managed by # ** the database connection. ^The value will be valid until the database N # ** is [DETACH]-ed or until the database connection closes. # ** # ** ^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. # ** # ** If the filename pointer returned by this routine is not NULL, then it # ** can be used as the filename input parameter to these routines: # ** # proc sqlite3_db_filename*(db: ptr sqlite3, zDbName: cstring): cstring {.impsqlite3C.} # # ** 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. # proc sqlite3_db_readonly*(db: ptr sqlite3, zDbName: cstring): cint {.impsqlite3C.} # # ** CAPI3REF: Determine the transaction state of a database # ** METHOD: sqlite3 # ** # ** ^The sqlite3_txn_state(D,S) interface returns the current # ** [transaction state] of schema S in database connection D. ^If S is NULL, # ** then the highest transaction state of any schema on database connection D # ** is returned. Transaction states are (in order of lowest to highest): # **
    # **
  1. SQLITE_TXN_NONE # **
  2. SQLITE_TXN_READ # **
  3. SQLITE_TXN_WRITE # **
# ** ^If the S argument to sqlite3_txn_state(D,S) is not the name of # ** a valid schema, then -1 is returned. # proc sqlite3_txn_state*(a1: ptr sqlite3, zSchema: cstring): cint {.impsqlite3C.} # # ** 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. # proc sqlite3_next_stmt*(pDb: ptr sqlite3, pStmt: ptr sqlite3_stmt): ptr sqlite3_stmt {.impsqlite3C.} # # ** 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. # # Declaration 'sqlite3_commit_hook' skipped # Declaration 'sqlite3_commit_hook' skipped # Declaration 'sqlite3_rollback_hook' skipped # Declaration 'sqlite3_rollback_hook' skipped # # ** 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_sequence).)^ # ** ^The update hook is not invoked when [WITHOUT ROWID] tables are modified. # ** # ** ^In the current implementation, the update hook # ** is not invoked when conflicting 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. # # Declaration 'sqlite3_update_hook' skipped # Declaration 'sqlite3_update_hook' skipped # # ** 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 to 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. It is recommended that it stay # ** that way. In other words, do not use this routine. This interface # ** continues to be provided for historical compatibility, but its use is # ** discouraged. Any use of shared cache is discouraged. If shared cache # ** must be used, it is recommended that shared cache only be enabled for # ** individual database connections using the [sqlite3_open_v2()] interface # ** with the [SQLITE_OPEN_SHAREDCACHE] flag. # ** # ** 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] # proc sqlite3_enable_shared_cache*(a1: cint): cint {.impsqlite3C.} # # ** 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()] # proc sqlite3_release_memory*(a1: cint): cint {.impsqlite3C.} # # ** 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()] # proc sqlite3_db_release_memory*(a1: ptr sqlite3): cint {.impsqlite3C.} # # ** CAPI3REF: Impose A Limit On Heap Size # ** # ** These interfaces impose limits on the amount of heap memory that will be # ** by all database connections within a single process. # ** # ** ^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 sqlite3_hard_heap_limit64(N) interface sets a hard upper bound of # ** N bytes on the amount of memory that will be allocated. ^The # ** sqlite3_hard_heap_limit64(N) interface is similar to # ** sqlite3_soft_heap_limit64(N) except that memory allocations will fail # ** when the hard heap limit is reached. # ** # ** ^The return value from both sqlite3_soft_heap_limit64() and # ** sqlite3_hard_heap_limit64() is the size of # ** the 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 heap limit. Hence, the current # ** size of heap limits can be determined by invoking # ** sqlite3_soft_heap_limit64(-1) or sqlite3_hard_heap_limit(-1). # ** # ** ^Setting the heap limits to zero disables the heap limiter mechanism. # ** # ** ^The soft heap limit may not be greater than the hard heap limit. # ** ^If the hard heap limit is enabled and if sqlite3_soft_heap_limit(N) # ** is invoked with a value of N that is greater than the hard heap limit, # ** the the soft heap limit is set to the value of the hard heap limit. # ** ^The soft heap limit is automatically enabled whenever the hard heap # ** limit is enabled. ^When sqlite3_hard_heap_limit64(N) is invoked and # ** the soft heap limit is outside the range of 1..N, then the soft heap # ** limit is set to N. ^Invoking sqlite3_soft_heap_limit64(0) when the # ** hard heap limit is enabled makes the soft heap limit equal to the # ** hard heap limit. # ** # ** The memory allocation limits can also be adjusted using # ** [PRAGMA soft_heap_limit] and [PRAGMA hard_heap_limit]. # ** # ** ^(The heap limits are not enforced in the current implementation # ** if one or more of following conditions are true: # ** # ** )^ # ** # ** The circumstances under which SQLite will enforce the heap limits may # ** changes in future releases of SQLite. # proc sqlite3_soft_heap_limit64*(N: int64): int64 {.impsqlite3C.} proc sqlite3_hard_heap_limit64*(N: int64): int64 {.impsqlite3C.} # # ** 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. # proc sqlite3_soft_heap_limit*(N: cint) {.impsqlite3C.} # # ** 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 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. If the table name parameter T in a call to # ** sqlite3_table_column_metadata(X,D,T,C,...) is NULL then the result is # ** undefined behavior. # ** # ** ^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. # ** # ** ^(
# ** # **
Parameter Output
Type
Description # ** # **
5th const char* Data type # **
6th const char* Name of default collation sequence # **
7th int True if column has a NOT NULL constraint # **
8th int True if column is part of the PRIMARY KEY # **
9th int True if column is [AUTOINCREMENT] # **
# **
)^ # ** # ** ^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: # ** # **
# **     data type: "INTEGER"
# **     collation sequence: "BINARY"
# **     not null: 0
# **     primary key: 1
# **     auto increment: 0
# ** 
)^ # ** # ** ^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. # proc sqlite3_table_column_metadata*(db: ptr sqlite3, zDbName: cstring, zTableName: cstring, zColumnName: cstring, pzDataType: ptr cstring, pzCollSeq: ptr cstring, pNotNull: ptr cint, pPrimaryKey: ptr cint, pAutoinc: ptr cint): cint {.impsqlite3C.} # # ** 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. # ** # ** Security warning: 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]. # proc sqlite3_load_extension*(db: ptr sqlite3, zFile: cstring, zProc: cstring, pzErrMsg: ptr cstring): cint {.impsqlite3C.} # # ** 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.)^ # ** # ** Security warning: It is recommended that extension loading # ** be enabled 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. # proc sqlite3_enable_load_extension*(db: ptr sqlite3, onoff: cint): cint {.impsqlite3C.} # # ** 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: # ** # **
# **    int xEntryPoint(
# **      sqlite3 *db,
# **      const char **pzErrMsg,
# **      const struct sqlite3_api_routines *pThunk
# **    );
# ** 
)^ # ** # ** 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()] # # Declaration 'sqlite3_auto_extension' skipped # Declaration 'sqlite3_auto_extension' skipped # Declaration 'xEntryPoint' skipped # # ** 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. # # Declaration 'sqlite3_cancel_auto_extension' skipped # Declaration 'sqlite3_cancel_auto_extension' skipped # Declaration 'xEntryPoint' skipped # # ** CAPI3REF: Reset Automatic Extension Loading # ** # ** ^This interface disables all automatic extensions previously # ** registered using [sqlite3_auto_extension()]. # proc sqlite3_reset_auto_extension*() {.impsqlite3C.} # # ** 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. # ** # ** ^If the third parameter (the pointer to the sqlite3_module object) is # ** NULL then no new module is create and any existing modules with the # ** same name are dropped. # ** # ** See also: [sqlite3_drop_modules()] # proc sqlite3_create_module*(db: ptr sqlite3, zName: cstring, p: ptr sqlite3_module, pClientData: pointer): cint {.impsqlite3C.} # Declaration 'sqlite3_create_module_v2' skipped # Declaration 'db' skipped # Declaration 'zName' skipped # Declaration 'p' skipped # Declaration 'pClientData' skipped # Declaration 'sqlite3_create_module_v2' skipped # Declaration 'db' skipped # Declaration 'zName' skipped # Declaration 'p' skipped # Declaration 'pClientData' skipped # Declaration 'xDestroy' skipped # # ** CAPI3REF: Remove Unnecessary Virtual Table Implementations # ** METHOD: sqlite3 # ** # ** ^The sqlite3_drop_modules(D,L) interface removes all virtual # ** table modules from database connection D except those named on list L. # ** The L parameter must be either NULL or a pointer to an array of pointers # ** to strings where the array is terminated by a single NULL pointer. # ** ^If the L parameter is NULL, then all virtual table modules are removed. # ** # ** See also: [sqlite3_create_module()] # proc sqlite3_drop_modules*(db: ptr sqlite3, azKeep: ptr cstring): cint {.impsqlite3C.} # # ** 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. # # # ** 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. # # # ** 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. # proc sqlite3_declare_vtab*(a1: ptr sqlite3, zSQL: cstring): cint {.impsqlite3C.} # # ** 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]. # proc sqlite3_overload_function*(a1: ptr sqlite3, zFuncName: cstring, nArg: cint): cint {.impsqlite3C.} # # ** 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: # ** # **
# **     SELECT zColumn FROM zDb.zTable WHERE [rowid] = iRow;
# ** 
)^ # ** # ** ^(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: # ** # ** # ** ^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. # ** # ** A BLOB referenced by sqlite3_blob_open() may be read using the # ** [sqlite3_blob_read()] interface and modified by using # ** [sqlite3_blob_write()]. The [BLOB handle] can be moved to a # ** different row of the same table using the [sqlite3_blob_reopen()] # ** interface. However, the column, table, or database of a [BLOB handle] # ** cannot be changed after the [BLOB handle] is opened. # ** # ** ^(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()]. # ** # ** See also: [sqlite3_blob_close()], # ** [sqlite3_blob_reopen()], [sqlite3_blob_read()], # ** [sqlite3_blob_bytes()], [sqlite3_blob_write()]. # proc sqlite3_blob_open*(a1: ptr sqlite3, zDb: cstring, zTable: cstring, zColumn: cstring, iRow: int64, flags: cint, ppBlob: ptr ptr sqlite3_blob): cint {.impsqlite3C.} # # ** 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 is # ** 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. # proc sqlite3_blob_reopen*(a1: ptr sqlite3_blob, a2: int64): cint {.impsqlite3C.} # # ** 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. # proc sqlite3_blob_close*(a1: ptr sqlite3_blob): cint {.impsqlite3C.} # # ** 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. # proc sqlite3_blob_bytes*(a1: ptr sqlite3_blob): cint {.impsqlite3C.} # # ** 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()]. # proc sqlite3_blob_read*(a1: ptr sqlite3_blob, Z: pointer, N: cint, iOffset: cint): cint {.impsqlite3C.} # # ** 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()]. # proc sqlite3_blob_write*(a1: ptr sqlite3_blob, z: pointer, n: cint, iOffset: cint): cint {.impsqlite3C.} # # ** 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.)^ # proc sqlite3_vfs_find*(zVfsName: cstring): ptr sqlite3_vfs {.impsqlite3C.} proc sqlite3_vfs_register*(a1: ptr sqlite3_vfs, makeDflt: cint): cint {.impsqlite3C.} proc sqlite3_vfs_unregister*(a1: ptr sqlite3_vfs): cint {.impsqlite3C.} # # ** 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: # ** # ** # ** # ** 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: # ** # ** # ** # ** ^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()]. # proc sqlite3_mutex_alloc*(a1: cint): ptr sqlite3_mutex {.impsqlite3C.} proc sqlite3_mutex_free*(a1: ptr sqlite3_mutex) {.impsqlite3C.} proc sqlite3_mutex_enter*(a1: ptr sqlite3_mutex) {.impsqlite3C.} proc sqlite3_mutex_try*(a1: ptr sqlite3_mutex): cint {.impsqlite3C.} proc sqlite3_mutex_leave*(a1: ptr sqlite3_mutex) {.impsqlite3C.} # # ** 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. # proc sqlite3_mutex_held*(a1: ptr sqlite3_mutex): cint {.impsqlite3C.} proc sqlite3_mutex_notheld*(a1: ptr sqlite3_mutex): cint {.impsqlite3C.} # # ** 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. # proc sqlite3_db_mutex*(a1: ptr sqlite3): ptr sqlite3_mutex {.impsqlite3C.} # # ** CAPI3REF: Low-Level Control Of Database Files # ** METHOD: sqlite3 # ** KEYWORDS: {file control} # ** # ** ^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. # ** # ** A few opcodes for [sqlite3_file_control()] are handled directly # ** by the SQLite core and never invoke the # ** sqlite3_io_methods.xFileControl method. # ** ^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_JOURNAL_POINTER] works similarly except that it returns # ** the [sqlite3_file] object associated with the journal file instead of # ** the main database. The [SQLITE_FCNTL_VFS_POINTER] opcode returns # ** a pointer to the underlying [sqlite3_vfs] object for the file. # ** The [SQLITE_FCNTL_DATA_VERSION] returns the data version counter # ** from the pager. # ** # ** ^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: [file control opcodes] # proc sqlite3_file_control*(a1: ptr sqlite3, zDbName: cstring, op: cint, a2: pointer): cint {.impsqlite3C.} # # ** 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. # proc sqlite3_test_control*(op: cint): cint {.impsqlite3C.} # # ** CAPI3REF: SQL Keyword Checking # ** # ** These routines provide access to the set of SQL language keywords # ** recognized by SQLite. Applications can uses these routines to determine # ** whether or not a specific identifier needs to be escaped (for example, # ** by enclosing in double-quotes) so as not to confuse the parser. # ** # ** The sqlite3_keyword_count() interface returns the number of distinct # ** keywords understood by SQLite. # ** # ** The sqlite3_keyword_name(N,Z,L) interface finds the N-th keyword and # ** makes *Z point to that keyword expressed as UTF8 and writes the number # ** of bytes in the keyword into *L. The string that *Z points to is not # ** zero-terminated. The sqlite3_keyword_name(N,Z,L) routine returns # ** SQLITE_OK if N is within bounds and SQLITE_ERROR if not. If either Z # ** or L are NULL or invalid pointers then calls to # ** sqlite3_keyword_name(N,Z,L) result in undefined behavior. # ** # ** The sqlite3_keyword_check(Z,L) interface checks to see whether or not # ** the L-byte UTF8 identifier that Z points to is a keyword, returning non-zero # ** if it is and zero if not. # ** # ** The parser used by SQLite is forgiving. It is often possible to use # ** a keyword as an identifier as long as such use does not result in a # ** parsing ambiguity. For example, the statement # ** "CREATE TABLE BEGIN(REPLACE,PRAGMA,END);" is accepted by SQLite, and # ** creates a new table named "BEGIN" with three columns named # ** "REPLACE", "PRAGMA", and "END". Nevertheless, best practice is to avoid # ** using keywords as identifiers. Common techniques used to avoid keyword # ** name collisions include: # ** # ** # ** Note that the number of keywords understood by SQLite can depend on # ** compile-time options. For example, "VACUUM" is not a keyword if # ** SQLite is compiled with the [-DSQLITE_OMIT_VACUUM] option. Also, # ** new keywords may be added to future releases of SQLite. # proc sqlite3_keyword_count*(): cint {.impsqlite3C.} proc sqlite3_keyword_name*(a1: cint, a2: ptr cstring, a3: ptr cint): cint {.impsqlite3C.} proc sqlite3_keyword_check*(a1: cstring, a2: cint): cint {.impsqlite3C.} # # ** CAPI3REF: Create A New Dynamic String Object # ** CONSTRUCTOR: sqlite3_str # ** # ** ^The [sqlite3_str_new(D)] interface allocates and initializes # ** a new [sqlite3_str] object. To avoid memory leaks, the object returned by # ** [sqlite3_str_new()] must be freed by a subsequent call to # ** [sqlite3_str_finish(X)]. # ** # ** ^The [sqlite3_str_new(D)] interface always returns a pointer to a # ** valid [sqlite3_str] object, though in the event of an out-of-memory # ** error the returned object might be a special singleton that will # ** silently reject new text, always return SQLITE_NOMEM from # ** [sqlite3_str_errcode()], always return 0 for # ** [sqlite3_str_length()], and always return NULL from # ** [sqlite3_str_finish(X)]. It is always safe to use the value # ** returned by [sqlite3_str_new(D)] as the sqlite3_str parameter # ** to any of the other [sqlite3_str] methods. # ** # ** The D parameter to [sqlite3_str_new(D)] may be NULL. If the # ** D parameter in [sqlite3_str_new(D)] is not NULL, then the maximum # ** length of the string contained in the [sqlite3_str] object will be # ** the value set for [sqlite3_limit](D,[SQLITE_LIMIT_LENGTH]) instead # ** of [SQLITE_MAX_LENGTH]. # proc sqlite3_str_new*(a1: ptr sqlite3): ptr sqlite3_str {.impsqlite3C.} # # ** CAPI3REF: Finalize A Dynamic String # ** DESTRUCTOR: sqlite3_str # ** # ** ^The [sqlite3_str_finish(X)] interface destroys the sqlite3_str object X # ** and returns a pointer to a memory buffer obtained from [sqlite3_malloc64()] # ** that contains the constructed string. The calling application should # ** pass the returned value to [sqlite3_free()] to avoid a memory leak. # ** ^The [sqlite3_str_finish(X)] interface may return a NULL pointer if any # ** errors were encountered during construction of the string. ^The # ** [sqlite3_str_finish(X)] interface will also return a NULL pointer if the # ** string in [sqlite3_str] object X is zero bytes long. # proc sqlite3_str_finish*(a1: ptr sqlite3_str): cstring {.impsqlite3C.} # # ** CAPI3REF: Add Content To A Dynamic String # ** METHOD: sqlite3_str # ** # ** These interfaces add content to an sqlite3_str object previously obtained # ** from [sqlite3_str_new()]. # ** # ** ^The [sqlite3_str_appendf(X,F,...)] and # ** [sqlite3_str_vappendf(X,F,V)] interfaces uses the [built-in printf] # ** functionality of SQLite to append formatted text onto the end of # ** [sqlite3_str] object X. # ** # ** ^The [sqlite3_str_append(X,S,N)] method appends exactly N bytes from string S # ** onto the end of the [sqlite3_str] object X. N must be non-negative. # ** S must contain at least N non-zero bytes of content. To append a # ** zero-terminated string in its entirety, use the [sqlite3_str_appendall()] # ** method instead. # ** # ** ^The [sqlite3_str_appendall(X,S)] method appends the complete content of # ** zero-terminated string S onto the end of [sqlite3_str] object X. # ** # ** ^The [sqlite3_str_appendchar(X,N,C)] method appends N copies of the # ** single-byte character C onto the end of [sqlite3_str] object X. # ** ^This method can be used, for example, to add whitespace indentation. # ** # ** ^The [sqlite3_str_reset(X)] method resets the string under construction # ** inside [sqlite3_str] object X back to zero bytes in length. # ** # ** These methods do not return a result code. ^If an error occurs, that fact # ** is recorded in the [sqlite3_str] object and can be recovered by a # ** subsequent call to [sqlite3_str_errcode(X)]. # proc sqlite3_str_appendf*(a1: ptr sqlite3_str, zFormat: cstring) {.impsqlite3C.} proc sqlite3_str_append*(a1: ptr sqlite3_str, zIn: cstring, N: cint) {.impsqlite3C.} proc sqlite3_str_appendall*(a1: ptr sqlite3_str, zIn: cstring) {.impsqlite3C.} proc sqlite3_str_appendchar*(a1: ptr sqlite3_str, N: cint, C: cchar) {.impsqlite3C.} proc sqlite3_str_reset*(a1: ptr sqlite3_str) {.impsqlite3C.} # # ** CAPI3REF: Status Of A Dynamic String # ** METHOD: sqlite3_str # ** # ** These interfaces return the current status of an [sqlite3_str] object. # ** # ** ^If any prior errors have occurred while constructing the dynamic string # ** in sqlite3_str X, then the [sqlite3_str_errcode(X)] method will return # ** an appropriate error code. ^The [sqlite3_str_errcode(X)] method returns # ** [SQLITE_NOMEM] following any out-of-memory error, or # ** [SQLITE_TOOBIG] if the size of the dynamic string exceeds # ** [SQLITE_MAX_LENGTH], or [SQLITE_OK] if there have been no errors. # ** # ** ^The [sqlite3_str_length(X)] method returns the current length, in bytes, # ** of the dynamic string under construction in [sqlite3_str] object X. # ** ^The length returned by [sqlite3_str_length(X)] does not include the # ** zero-termination byte. # ** # ** ^The [sqlite3_str_value(X)] method returns a pointer to the current # ** content of the dynamic string under construction in X. The value # ** returned by [sqlite3_str_value(X)] is managed by the sqlite3_str object X # ** and might be freed or altered by any subsequent method on the same # ** [sqlite3_str] object. Applications must not used the pointer returned # ** [sqlite3_str_value(X)] after any subsequent method call on the same # ** object. ^Applications may change the content of the string returned # ** by [sqlite3_str_value(X)] as long as they do not write into any bytes # ** outside the range of 0 to [sqlite3_str_length(X)] and do not read or # ** write any byte after any subsequent sqlite3_str method call. # proc sqlite3_str_errcode*(a1: ptr sqlite3_str): cint {.impsqlite3C.} proc sqlite3_str_length*(a1: ptr sqlite3_str): cint {.impsqlite3C.} proc sqlite3_str_value*(a1: ptr sqlite3_str): cstring {.impsqlite3C.} # # ** 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()] # proc sqlite3_status*(op: cint, pCurrent: ptr cint, pHighwater: ptr cint, resetFlag: cint): cint {.impsqlite3C.} proc sqlite3_status64*(op: cint, pCurrent: ptr int64, pHighwater: ptr int64, resetFlag: cint): cint {.impsqlite3C.} # # ** 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()]. # proc sqlite3_db_status*(a1: ptr sqlite3, op: cint, pCur: ptr cint, pHiwtr: ptr cint, resetFlg: cint): cint {.impsqlite3C.} # # ** 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()]. # proc sqlite3_stmt_status*(a1: ptr sqlite3_stmt, op: cint, resetFlg: cint): cint {.impsqlite3C.} # # ** 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: # **
    # **
  1. sqlite3_backup_init() is called once to initialize the # ** backup, # **
  2. sqlite3_backup_step() is called one or more times to transfer # ** the data between the two databases, and finally # **
  3. sqlite3_backup_finish() is called to release all resources # ** associated with the backup operation. # **
)^ # ** There should be exactly one call to sqlite3_backup_finish() for each # ** successful call to sqlite3_backup_init(). # ** # ** [[sqlite3_backup_init()]] sqlite3_backup_init() # ** # ** ^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()]] sqlite3_backup_step() # ** # ** ^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 # **
    # **
  1. the destination database was opened read-only, or # **
  2. the destination database is using write-ahead-log journaling # ** and the destination and source page sizes differ, or # **
  3. the destination database is an in-memory database and the # ** destination and source page sizes differ. # **
)^ # ** # ** ^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()]] sqlite3_backup_finish() # ** # ** 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()]] # ** sqlite3_backup_remaining() and sqlite3_backup_pagecount() # ** # ** ^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().)^ # ** # ** Concurrent Usage of Database Handles # ** # ** ^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. # proc sqlite3_backup_init*(pDest: ptr sqlite3, zDestName: cstring, pSource: ptr sqlite3, zSourceName: cstring): ptr sqlite3_backup {.impsqlite3C.} proc sqlite3_backup_step*(p: ptr sqlite3_backup, nPage: cint): cint {.impsqlite3C.} proc sqlite3_backup_finish*(p: ptr sqlite3_backup): cint {.impsqlite3C.} proc sqlite3_backup_remaining*(p: ptr sqlite3_backup): cint {.impsqlite3C.} proc sqlite3_backup_pagecount*(p: ptr sqlite3_backup): cint {.impsqlite3C.} # # ** 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 connection's 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. # ** # ** Callback Invocation Details # ** # ** 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 connection's 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. # ** # ** Deadlock Detection # ** # ** 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. # ** # ** The "DROP TABLE" Exception # ** # ** 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.)^ # # Declaration 'sqlite3_unlock_notify' skipped # Declaration 'pBlocked' skipped # Declaration 'sqlite3_unlock_notify' skipped # Declaration 'pBlocked' skipped # Declaration 'xNotify' skipped # Declaration 'apArg' skipped # Declaration 'nArg' skipped # Declaration 'pNotifyArg' skipped # # ** 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. # proc sqlite3_stricmp*(a1: cstring, a2: cstring): cint {.impsqlite3C.} proc sqlite3_strnicmp*(a1: cstring, a2: cstring, a3: cint): cint {.impsqlite3C.} # # ** 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()]. # proc sqlite3_strglob*(zGlob: cstring, zStr: cstring): cint {.impsqlite3C.} # # ** 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()]. # proc sqlite3_strlike*(zGlob: cstring, zStr: cstring, cEsc: cuint): cint {.impsqlite3C.} # # ** 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. # proc sqlite3_log*(iErrCode: cint, zFormat: cstring) {.impsqlite3C.} # # ** 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. # # Declaration 'sqlite3_wal_hook' skipped # Declaration 'sqlite3_wal_hook' skipped # # ** 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. # proc sqlite3_wal_autocheckpoint*(db: ptr sqlite3, N: cint): cint {.impsqlite3C.} # # ** 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()]. # proc sqlite3_wal_checkpoint*(db: ptr sqlite3, zDb: cstring): cint {.impsqlite3C.} # # ** 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]:)^ # ** # **
# **
SQLITE_CHECKPOINT_PASSIVE
# ** ^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. # ** # **
SQLITE_CHECKPOINT_FULL
# ** ^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. # ** # **
SQLITE_CHECKPOINT_RESTART
# ** ^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. # ** # **
SQLITE_CHECKPOINT_TRUNCATE
# ** ^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. # **
# ** # ** ^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. # proc sqlite3_wal_checkpoint_v2*(db: ptr sqlite3, zDb: cstring, eMode: cint, pnLog: ptr cint, pnCkpt: ptr cint): cint {.impsqlite3C.} # # ** 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. # ** # ** In the call sqlite3_vtab_config(D,C,...) the D parameter is the # ** [database connection] in which the virtual table is being created and # ** which is passed in as the first argument to the [xConnect] or [xCreate] # ** method that is invoking sqlite3_vtab_config(). The C parameter is one # ** of the [virtual table configuration options]. The presence and meaning # ** of parameters after C depend on which [virtual table configuration option] # ** is used. # proc sqlite3_vtab_config*(a1: ptr sqlite3, op: cint): cint {.impsqlite3C.} # # ** 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]. # proc sqlite3_vtab_on_conflict*(a1: ptr sqlite3): cint {.impsqlite3C.} # # ** CAPI3REF: Determine If Virtual Table Column Access Is For UPDATE # ** # ** If the sqlite3_vtab_nochange(X) routine is called within the [xColumn] # ** method of a [virtual table], then it might return true if the # ** column is being fetched as part of an UPDATE operation during which the # ** column value will not change. The virtual table implementation can use # ** this hint as permission to substitute a return value that is less # ** expensive to compute and that the corresponding # ** [xUpdate] method understands as a "no-change" value. # ** # ** If the [xColumn] method calls sqlite3_vtab_nochange() and finds that # ** the column is not changed by the UPDATE statement, then the xColumn # ** method can optionally return without setting a result, without calling # ** any of the [sqlite3_result_int|sqlite3_result_xxxxx() interfaces]. # ** In that case, [sqlite3_value_nochange(X)] will return true for the # ** same column in the [xUpdate] method. # ** # ** The sqlite3_vtab_nochange() routine is an optimization. Virtual table # ** implementations should continue to give a correct answer even if the # ** sqlite3_vtab_nochange() interface were to always return false. In the # ** current implementation, the sqlite3_vtab_nochange() interface does always # ** returns false for the enhanced [UPDATE FROM] statement. # proc sqlite3_vtab_nochange*(a1: ptr sqlite3_context): cint {.impsqlite3C.} # # ** CAPI3REF: Determine The Collation For a Virtual Table Constraint # ** # ** This function may only be called from within a call to the [xBestIndex] # ** method of a [virtual table]. # ** # ** The first argument must be the sqlite3_index_info object that is the # ** first parameter to the xBestIndex() method. The second argument must be # ** an index into the aConstraint[] array belonging to the sqlite3_index_info # ** structure passed to xBestIndex. This function returns a pointer to a buffer # ** containing the name of the collation sequence for the corresponding # ** constraint. # proc sqlite3_vtab_collation*(a1: ptr sqlite3_index_info, a2: cint): cstring {.impsqlite3C.} # # ** 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()] # proc sqlite3_stmt_scanstatus*(pStmt: ptr sqlite3_stmt, idx: cint, iScanStatusOp: cint, pOut: pointer): cint {.impsqlite3C.} # # ** 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. # proc sqlite3_stmt_scanstatus_reset*(a1: ptr sqlite3_stmt) {.impsqlite3C.} # # ** CAPI3REF: Flush caches to disk mid-transaction # ** METHOD: sqlite3 # ** # ** ^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. # proc sqlite3_db_cacheflush*(a1: ptr sqlite3): cint {.impsqlite3C.} # # ** CAPI3REF: The pre-update hook. # ** METHOD: sqlite3 # ** # ** ^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 database 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 real database tables; the # ** preupdate hook is not invoked for changes to [virtual tables] or to # ** system tables like sqlite_sequence or sqlite_stat1. # ** # ** ^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. # ** # ** For an UPDATE or DELETE operation on a [rowid table], the sixth # ** parameter passed to the preupdate callback is the initial [rowid] of the # ** row being modified or deleted. For an INSERT operation on a rowid table, # ** or any operation on a WITHOUT ROWID table, the value of the sixth # ** parameter is undefined. For an INSERT or UPDATE on a rowid table the # ** seventh parameter is the final rowid value of the row being inserted # ** or updated. The value of the seventh parameter passed to the callback # ** function is not defined for operations on WITHOUT ROWID tables, or for # ** DELETE operations on rowid tables. # ** # ** 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()] # # # ** CAPI3REF: Low-level system error code # ** METHOD: sqlite3 # ** # ** ^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. # proc sqlite3_system_errno*(a1: ptr sqlite3): cint {.impsqlite3C.} # # ** CAPI3REF: Record A Database Snapshot # ** CONSTRUCTOR: sqlite3_snapshot # ** # ** ^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 there is not already a read-transaction open on schema S when # ** this function is called, one is opened automatically. # ** # ** The following must be true for this function to succeed. If any of # ** the following statements are false when sqlite3_snapshot_get() is # ** called, SQLITE_ERROR is returned. The final value of *P is undefined # ** in this case. # ** # ** # ** # ** This function may also return SQLITE_NOMEM. If it is called with the # ** database handle in autocommit mode but fails for some other reason, # ** whether or not a read transaction is opened on schema S is undefined. # ** # ** 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. # proc sqlite3_snapshot_get*(db: ptr sqlite3, zSchema: cstring, ppSnapshot: ptr ptr sqlite3_snapshot): cint {.impsqlite3C.} # # ** CAPI3REF: Start a read transaction on an historical snapshot # ** METHOD: sqlite3_snapshot # ** # ** ^The [sqlite3_snapshot_open(D,S,P)] interface either starts a new read # ** transaction or upgrades an existing one 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, the database connection must not be in # ** [autocommit mode] when [sqlite3_snapshot_open(D,S,P)] is called. If there # ** is already a read transaction open on schema S, then the database handle # ** must have no active statements (SELECT statements that have been passed # ** to sqlite3_step() but not sqlite3_reset() or sqlite3_finalize()). # ** SQLITE_ERROR is returned if either of these conditions is violated, or # ** if schema S does not exist, or if the snapshot object is invalid. # ** # ** ^A call to sqlite3_snapshot_open() will fail to open if the specified # ** snapshot has been overwritten by a [checkpoint]. In this case # ** SQLITE_ERROR_SNAPSHOT is returned. # ** # ** If there is already a read transaction open when this function is # ** invoked, then the same read transaction remains open (on the same # ** database snapshot) if SQLITE_ERROR, SQLITE_BUSY or SQLITE_ERROR_SNAPSHOT # ** is returned. If another error code - for example SQLITE_PROTOCOL or an # ** SQLITE_IOERR error code - is returned, then the final state of the # ** read transaction is undefined. If SQLITE_OK is returned, then the # ** read transaction is now open on database snapshot P. # ** # ** ^(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. # proc sqlite3_snapshot_open*(db: ptr sqlite3, zSchema: cstring, pSnapshot: ptr sqlite3_snapshot): cint {.impsqlite3C.} # # ** CAPI3REF: Destroy a snapshot # ** DESTRUCTOR: sqlite3_snapshot # ** # ** ^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. # proc sqlite3_snapshot_free*(a1: ptr sqlite3_snapshot) {.impsqlite3C.} # # ** CAPI3REF: Compare the ages of two snapshot handles. # ** METHOD: sqlite3_snapshot # ** # ** 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. # ** # ** This interface is only available if SQLite is compiled with the # ** [SQLITE_ENABLE_SNAPSHOT] option. # proc sqlite3_snapshot_cmp*(p1: ptr sqlite3_snapshot, p2: ptr sqlite3_snapshot): cint {.impsqlite3C.} # # ** CAPI3REF: Recover snapshots from a wal file # ** METHOD: sqlite3_snapshot # ** # ** If a [WAL file] remains on disk after all database connections close # ** (either through the use of the [SQLITE_FCNTL_PERSIST_WAL] [file control] # ** or because the last process to have the database opened exited without # ** calling [sqlite3_close()]) and a new connection is subsequently opened # ** on that database and [WAL file], the [sqlite3_snapshot_open()] interface # ** will only be able to open the last transaction added to the WAL file # ** even though the WAL file contains other valid transactions. # ** # ** This function attempts to scan the WAL file associated with database zDb # ** of database handle db and make all valid snapshots available to # ** sqlite3_snapshot_open(). It is an error if there is already a read # ** transaction open on the database, or if the database is not a WAL mode # ** database. # ** # ** SQLITE_OK is returned if successful, or an SQLite error code otherwise. # ** # ** This interface is only available if SQLite is compiled with the # ** [SQLITE_ENABLE_SNAPSHOT] option. # proc sqlite3_snapshot_recover*(db: ptr sqlite3, zDb: cstring): cint {.impsqlite3C.} # # ** CAPI3REF: Serialize a database # ** # ** The sqlite3_serialize(D,S,P,F) interface returns a pointer to memory # ** that is a serialization of the S database on [database connection] D. # ** If P is not a NULL pointer, then the size of the database in bytes # ** is written into *P. # ** # ** For an ordinary on-disk database file, the serialization is just a # ** copy of the disk file. For an in-memory database or a "TEMP" database, # ** the serialization is the same sequence of bytes which would be written # ** to disk if that database where backed up to disk. # ** # ** The usual case is that sqlite3_serialize() copies the serialization of # ** the database into memory obtained from [sqlite3_malloc64()] and returns # ** a pointer to that memory. The caller is responsible for freeing the # ** returned value to avoid a memory leak. However, if the F argument # ** contains the SQLITE_SERIALIZE_NOCOPY bit, then no memory allocations # ** are made, and the sqlite3_serialize() function will return a pointer # ** to the contiguous memory representation of the database that SQLite # ** is currently using for that database, or NULL if the no such contiguous # ** memory representation of the database exists. A contiguous memory # ** representation of the database will usually only exist if there has # ** been a prior call to [sqlite3_deserialize(D,S,...)] with the same # ** values of D and S. # ** The size of the database is written into *P even if the # ** SQLITE_SERIALIZE_NOCOPY bit is set but no contiguous copy # ** of the database exists. # ** # ** A call to sqlite3_serialize(D,S,P,F) might return NULL even if the # ** SQLITE_SERIALIZE_NOCOPY bit is omitted from argument F if a memory # ** allocation error occurs. # ** # ** This interface is only available if SQLite is compiled with the # ** [SQLITE_ENABLE_DESERIALIZE] option. # proc sqlite3_serialize*(db: ptr sqlite3, zSchema: cstring, piSize: ptr int64, mFlags: cuint): ptr cuchar {.impsqlite3C.} # # ** CAPI3REF: Deserialize a database # ** # ** The sqlite3_deserialize(D,S,P,N,M,F) interface causes the # ** [database connection] D to disconnect from database S and then # ** reopen S as an in-memory database based on the serialization contained # ** in P. The serialized database P is N bytes in size. M is the size of # ** the buffer P, which might be larger than N. If M is larger than N, and # ** the SQLITE_DESERIALIZE_READONLY bit is not set in F, then SQLite is # ** permitted to add content to the in-memory database as long as the total # ** size does not exceed M bytes. # ** # ** If the SQLITE_DESERIALIZE_FREEONCLOSE bit is set in F, then SQLite will # ** invoke sqlite3_free() on the serialization buffer when the database # ** connection closes. If the SQLITE_DESERIALIZE_RESIZEABLE bit is set, then # ** SQLite will try to increase the buffer size using sqlite3_realloc64() # ** if writes on the database cause it to grow larger than M bytes. # ** # ** The sqlite3_deserialize() interface will fail with SQLITE_BUSY if the # ** database is currently in a read transaction or is involved in a backup # ** operation. # ** # ** If sqlite3_deserialize(D,S,P,N,M,F) fails for any reason and if the # ** SQLITE_DESERIALIZE_FREEONCLOSE bit is set in argument F, then # ** [sqlite3_free()] is invoked on argument P prior to returning. # ** # ** This interface is only available if SQLite is compiled with the # ** [SQLITE_ENABLE_DESERIALIZE] option. # proc sqlite3_deserialize*(db: ptr sqlite3, zSchema: cstring, pData: ptr cuchar, szDb: int64, szBuf: int64, mFlags: cuint): cint {.impsqlite3C.} # # ** Register a geometry callback named zGeom that can be used as part of an # ** R-Tree geometry query as follows: # ** # ** SELECT ... FROM WHERE MATCH $zGeom(... params ...) # # Declaration 'sqlite3_rtree_geometry_callback' skipped # Declaration 'db' skipped # Declaration 'zGeom' skipped # Declaration 'sqlite3_rtree_geometry_callback' skipped # Declaration 'db' skipped # Declaration 'zGeom' skipped # Declaration 'xGeom' skipped # Declaration 'pContext' skipped # # ** A pointer to a structure of the following type is passed as the first # ** argument to callbacks registered using rtree_geometry_callback(). # # # ** Register a 2nd-generation geometry callback named zScore that can be # ** used as part of an R-Tree geometry query as follows: # ** # ** SELECT ... FROM WHERE MATCH $zQueryFunc(... params ...) # # Declaration 'sqlite3_rtree_query_callback' skipped # Declaration 'db' skipped # Declaration 'zQueryFunc' skipped # Declaration 'sqlite3_rtree_query_callback' skipped # Declaration 'db' skipped # Declaration 'zQueryFunc' skipped # Declaration 'xQueryFunc' skipped # Declaration 'pContext' skipped # Declaration 'xDestructor' skipped {.compile: "sqlite3.c".}