Thanks for all of your help. The problem was that the result_entry table had some constraints that pointed to a third table. When I removed those constraints the performance was amazing. The update took less than seven minutes to execute. I did not even consider the fact that constraints to another table would impact the performance. Thanks again, Lance Campbell Project Manager/Software Architect Web Services at Public Affairs University of Illinois 217.333.0382 http://webservices.uiuc.edu -----Original Message----- From: pgsql-performance-owner@xxxxxxxxxxxxxx [mailto:pgsql-performance-owner@xxxxxxxxxxxxxx] On Behalf Of Gregory Stark Sent: Friday, October 26, 2007 9:05 PM To: Joshua D. Drake Cc: Campbell, Lance; pgsql-performance@xxxxxxxxxxxxxx Subject: Re: Suggestions on an update query "Joshua D. Drake" <jd@xxxxxxxxxxxxxxxxx> writes: > On Fri, 26 Oct 2007 15:31:44 -0500 > "Campbell, Lance" <lance@xxxxxxxx> wrote: > >> I forgot to include an additional parameter I am using in >> Postgresql.conf: >> > > O.k. first, just to get it out of the way (and then I will try and > help). Please do not top post, it makes replying contextually very > difficult. > >> PostgreSql version 8.2.4 >> >> Memory = 8 Gig >> >> CPUs 1 dual core Zeon running at 3.0 >> > > O.k. first you might be grinding through your 20 checkpoint segments > but in reality what I think is happening is you are doing foreign key > checks against all of it and slowing things down. If you're going to berate someone about top-posting perhaps you should attach your own commentary to relevant bits of context :P But the original post didn't include any foreign key constraints. I suspect you've guessed it right though. In fact I suspect what's happening is he doesn't have an index on the referencing column so the foreign key checks are doing sequential scans of. -- Gregory Stark EnterpriseDB http://www.enterprisedb.com ---------------------------(end of broadcast)--------------------------- TIP 4: Have you searched our list archives? http://archives.postgresql.org ---------------------------(end of broadcast)--------------------------- TIP 7: You can help support the PostgreSQL project by donating at http://www.postgresql.org/about/donate
