Re: Does TRUNCATE emit changes with REPLICA IDENTITY FULL?

Michael Paquier <[email protected]> Tue, 12 Nov 2019 09:44:32 +0900

Newsgroups	gmane.comp.db.postgresql.devel.documentation
Message-ID	<[email protected]>

On Mon, Nov 11, 2019 at 09:19:52AM +0000, PG Doc comments form wrote:
> The documentation says that TRUNCATE ignores ON DELETE triggers, but it
> doesn't explicitly mention what happens if we use `wal_level = logical` and
> `REPLICA IDENTITY FULL`. Does TRUNCATE emit changes for each row and clog
> the WAL, or will it still be blazing fast?

Truncate does not issue per-row changes with a full replica identity
in this context.  It roughly just takes an exclusive lock on the
table, then physically removes all the files related to the table.
--
Michael

signature.asc (application/pgp-signature, 833 B)