On 2014-03-17 20:51:31 -0300, Alvaro Herrera wrote: > > I think the best way to really cleanup a table is to use something like: > > ALTER TABLE rew ALTER COLUMN data TYPE text USING (data); > > where text is the previous type of the column. That should trigger a > > full table rewrite, without any finesse about tracking ctid chains. > > Isn't this what VACUUM FULL does?
No, it uses rewriteheap.c via cluster.c, which tries to preserve visibility information. There's tracking/mapping of t_ctid... I am not entirely sure how much it preserves, but I am not really hopeful. Greetings, Andres Freund -- Andres Freund http://www.2ndQuadrant.com/ PostgreSQL Development, 24x7 Support, Training & Services -- Sent via pgsql-hackers mailing list (email@example.com) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers