I'd been wondering why a VACUUM FREEZE is performed during pg_upgrade, so I opened up the code to see if that would help me determine why this is.
I'm confronted with a comment, which states; /* * We do freeze after analyze so pg_statistic is also frozen. template0 is * not frozen here, but data rows were frozen by initdb, and we set its * datfrozenxid, relfrozenxids, and relminmxid later to match the new xid * counter later. */ this is not helping me much as I don't really understand why pg_statistic need to be frozen? -- David Rowley http://www.2ndQuadrant.com/ PostgreSQL Development, 24x7 Support, Training & Services -- Sent via pgsql-hackers mailing list (firstname.lastname@example.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers