> Correct. The problem actually are aborted transactions. Just because an > XID is really old doesn't mean it was committed.
Yes, that's the main issue with my idea; XIDs which fell off the CLOG would become visible even if they'd aborted. Do we get a bit in the visibility map for a page which has aborted transaction rows on it? -- -- Josh Berkus PostgreSQL Experts Inc. http://www.pgexperts.com -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers