Re: autovacuum and temp tables support
Robert Haas <robertmhaas@gmail.com>
From: Robert Haas <robertmhaas@gmail.com>
To: Alvaro Herrera <alvherre@commandprompt.com>
Cc: Oleg Bartunov <oleg@sai.msu.su>, Pgsql Hackers <pgsql-hackers@postgresql.org>
Date: 2010-04-08T19:06:52Z
Lists: pgsql-hackers
On Thu, Apr 8, 2010 at 2:53 PM, Alvaro Herrera <alvherre@commandprompt.com> wrote: > Oleg Bartunov wrote: > >> our client complained about slow query, which involves temporary tables. >> Analyzing them manually solved the problem. I don't remember >> arguments against temporary tables support by autovacuum. I'd >> appreciate any >> pointers. > > Autovacuum can't process temp tables; they could reside in a backend's > private temp buffers (local memory, not shared). On general thought I've had is that it would be nice if the first attempt to SELECT against a table with no statistics would trigger an automatic ANALYZE by the backend on which the query was executed. It's pretty common to populate a table using INSERT, or CTAS, or COPY and then try to immediately run a query against it, and I've often found that it's necessary to insert manual analyze statements in there to get decent query plans. ...Robert