Re: Suggestions on an update query - Mailing list pgsql-performance

From Gregory Stark
Subject Re: Suggestions on an update query
Date
Msg-id 87odel1feo.fsf@oxford.xeocode.com
Whole thread Raw
In response to Re: Suggestions on an update query  ("Joshua D. Drake" <jd@commandprompt.com>)
Responses Re: Suggestions on an update query
Re: Suggestions on an update query
List pgsql-performance
"Joshua D. Drake" <jd@commandprompt.com> writes:

> On Fri, 26 Oct 2007 15:31:44 -0500
> "Campbell, Lance" <lance@uiuc.edu> 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

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