Question regarding temp tables.... If I (user=joe) attach and run something that uses a temp table, then I (user=joe again) attach again in another session, will there be 2 distinct temp tables? Or does one user get one temp table per DB? -----Original Message----- From: pgsql-general-owner@xxxxxxxxxxxxxx [mailto:pgsql-general-owner@xxxxxxxxxxxxxx] On Behalf Of Richard Huxton Sent: Monday, October 15, 2007 5:32 AM To: Jimmy Choi Cc: pgsql-general@xxxxxxxxxxxxxx Subject: Re: Guideline on use of temporary tables Jimmy Choi wrote: > I would like to use temporary table as a caching mechanism to speed up > queries within the same session. > Is this what temporary table is designed for? Are there caveats that I > should be aware of? Can you think of other better alternatives? It's a very common usage of temporary tables. Another is when loading data that you want to process / split up. Bear in mind that a temporary table is private to a particular backend, so if you had 100 connections all using a temporary table for the same query, that could be 100 copies of the data - not necessarily a performance improvement. Also, temporary tables have real entries in the system-tables, so make sure autovacuum (or your manual vacuums) are scanning pg_class etc often enough. -- Richard Huxton Archonet Ltd ---------------------------(end of broadcast)--------------------------- TIP 6: explain analyze is your friend ---------------------------(end of broadcast)--------------------------- TIP 6: explain analyze is your friend
