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0 pointslxgr11mo ago0 comments

Even worse: SQLite, by default, does not immediately truncate WAL files, but rather overwrites the existing WAL from the beginning after successfully applying a checksum.

Doing what the author suggests would actually introduce data corruption errors when "restoring a WAL with a broken checksum".

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2 comments · 1 top-level

avinassh11mo ago· 1 in thread

However, SQLite, by default, always truncates the WAL files on last connection close

> When the last connection to a database closes, that connection does one last checkpoint and then deletes the WAL and its associated shared-memory file, to clean up the disk.

https://www.sqlite.org/wal.html

lxgrOP11mo ago

Yes, but you can't rely on an orderly database close when it comes to correctness. Non-clean shutdowns are much more common than actual low-level data corruption in many SQLite applications.

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