From: Richard Huxton <dev@archonet.com>
To: Chris <dmagick@gmail.com>
Cc: Tom Lane <tgl@sss.pgh.pa.us>
Cc: Pgsql performance <pgsql-performance@postgresql.org>
Subject: Re: update query taking too long
Date: Thu, 28 Jun 2007 08:02:44 +0100
Message-ID: <46835D14.6010507@archonet.com> (raw)
In-Reply-To: <46835A16.3050602@gmail.com>
References: <46834124.5010600@gmail.com>
<21072.1183009270@sss.pgh.pa.us>
<46835252.5070901@gmail.com>
<468357B2.1040205@archonet.com>
<46835A16.3050602@gmail.com>
Chris wrote:
> db=# UPDATE email_upd_test SET domainname=substring(email from
> position('@' in email));
> UPDATE 1000000
> Time: 43796.030 ms
>
> I think I'm I/O bound from my very limited understanding of vmstat.
Well, 43 seconds to update 1 million rows suggests your real query
should be complete in a few minutes, even if your real table has more
columns.
Could you check again and just make sure you don't have a foreign key
referencing this table? I suspect a large table without an index on the
referencing column.
If you can't see anything, cancel the long-running query, run VACUUM
FULL VERBOSE on the table, ANALYSE VERBOSE and then try it again.
There's something very odd here.
--
Richard Huxton
Archonet Ltd
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To: pgsql-performance@postgresql.org
Cc: dev@archonet.com, dmagick@gmail.com, tgl@sss.pgh.pa.us
Subject: Re: update query taking too long
In-Reply-To: <46835D14.6010507@archonet.com>
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