From: Chris <dmagick@gmail.com>
To: Pgsql performance <pgsql-performance@postgresql.org>
Subject: update query taking too long
Date: Thu, 28 Jun 2007 15:03:32 +1000
Message-ID: <46834124.5010600@gmail.com> (raw)
Hi all,
I'm trying to do an update of a reasonably large table and it's taking
way too long so I'm trying to work out why and if I need to tweak any
settings to speed it up.
The table is around 3.5 million records.
The query is
update table set domainname=substring(emailaddress from position('@' in
emailaddress));
I've left it running for over 20 minutes and it hasn't finished so I'm
doing something terribly bad but I have no idea what ;)
Maybe there's another way to write the query but I'm not sure how to
make it better.
Most settings are default, I have bumped up shared_buffers a bit to
65536 - I think that works out to 512Meg ? The machine has 2G ram.
Running version 8.1.9.
Any pointers about settings etc are most welcome.
--
Postgresql & php tutorials
http://www.designmagick.com/
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To: pgsql-performance@postgresql.org
Cc: dmagick@gmail.com
Subject: Re: update query taking too long
In-Reply-To: <46834124.5010600@gmail.com>
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