Glossary
WAL checkpoint
The SQLite operation that copies committed pages from the write-ahead log back into the main database file, after which the WAL can be reset and reused.
A checkpoint moves committed transactions from the -wal file into the database. SQLite runs one automatically when a commit makes the WAL exceed 1,000 pages by default, and the last connection to close normally checkpoints and deletes the WAL (sqlite.org).
Forensically, checkpoints decide where evidence sits: before one, recent rows exist only in the WAL; after one, they are in the database. Opening original evidence with a normal SQLite client can trigger a checkpoint and alter the files. See why ActivitiesCache.db-wal matters.