sqlite3_snapshot_recover()

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 ... 

This document describes low-level details on how WAL mode is implemented on unix and windows. The separate file format description provides details on the structure of a database file and of the write-head log file used in WAL ... 

3. Activating And Configuring WAL Mode  ... To convert to WAL mode, use the following pragma: PRAGMA journal_mode=WAL; The journal_mode pragma returns a string which is the new journal mode. On success, the pragma will return the string "wal". If the conversion to WAL could not ... 

sqlite3_filename_database(), sqlite3_filename_journal(), sqlite3_filename_wal()

These routines are available to 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 ... 

sqlite3_snapshot_get()

 ... One or more transactions must have been written to the current wal file since it was created on disk (by any connection). This means that a snapshot cannot be taken on a wal mode database with no wal file immediately ... 

sqlite3_snapshot_cmp()

 ... 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 ... 

 ... For example, WAL mode was added in version 3.7.0 (2010-07-21). SQLite 3.7.0 and later can read and write all database files created by earlier versions of SQLite. And earlier versions of SQLite can read ... 

sqlite3_snapshot_open()

 ... 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 ... 

struct 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 ... 

sqlite3_wal_checkpoint_v2()

 ... 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 ...