Huan Ruan <leohuanruan@xxxxxxxxx> writes: > Let's say at T0 a database has N session based temp tables. They would have > corresponding records in the catalog tables like pg_class and pg_attribute > that are visible to other sessions. > At T1, I do a PITR to T0. That recovered database should not have those > temp tables because the sessions they were created in are not present. My > question is what events trigger the deletion of those temp tables' catalog > records (e.g. pg_class and pg_attribute etc.) in the recovered database? Those records will still be there in the catalogs, yes. Cleaning out the contents of a temporary schema is not the responsibility of the WAL/recovery system. It's done by live backends at two times: 1. A session that has used a temp schema will normally clean out the contained objects when it exits. 2. As a backstop in case #1 fails, a session that is about to begin using a temp schema will clean out any surviving contents. So if you rewound to a point where some temp objects exist, it'd be the responsibility of the first session that wants to use a given temp schema to clean out those objects. regards, tom lane
