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_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 ... 

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 ... 

 ... 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 ... 

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_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 ... 

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 ...