SQLite prefixes its temp files with `etilqs_`
This post documents a small but concrete SQLite implementation detail: temporary files created during operations like VACUUM are prefixed with etilqs_, which is simply sqlite_ spelled backwards. VACUUM rebuilds the database into a fresh temporary file to reclaim free space and defragment pages, so the prefix appears in SQLite’s temp-file creation path rather than in user-visible database names. The article cites the upstream src/os.h comment explaining that SQLite changed the default prefix in 2006 after McAfee-created temp files with sqlite in the name caused Windows users to misattribute those files to SQLite and contact the developers. It is mainly useful as implementation and debugging context for anyone studying SQLite-compatible engines or filesystem artifacts produced during database maintenance.