From: Reinoud van Leeuwen <reinoud.v@n.leeuwen.net>
To: pgsql-sql@postgresql.org
Subject: Re: Question on COUNT performance
Date: Wed, 14 Jul 2010 14:30:29 +0200
Message-ID: <20100714123029.GH62243@spoetnik.xs4all.nl> (raw)
In-Reply-To: <AANLkTimyhXoid1bAk2FQZUx9TC3Qgh2Ba__-Fu4B8Bco@mail.gmail.com>
References: <AANLkTimyhXoid1bAk2FQZUx9TC3Qgh2Ba__-Fu4B8Bco@mail.gmail.com>
On Wed, Jul 14, 2010 at 09:58:10PM +1000, Anders ??stergaard Jensen wrote:
> Hello mailing list,
>
> I have a performance problem with my postgres 8.4.4 database. The query is
> the following:
>
> SELECT count(*) AS count_all FROM "plan_events" WHERE (f_plan_event_acl(17,
> plan_events.id))
>
> QUERY PLAN
>
> ------------------------------------------------------------------------------------------------------------------------
> Aggregate (cost=2859.77..2859.78 rows=1 width=0) (actual
> time=4641.720..4641.720 rows=1 loops=1)
> -> Seq Scan on plan_events (cost=0.00..2851.44 rows=3331 width=0)
> (actual time=32.821..4640.116 rows=2669 loops=1)
> Filter: f_plan_event_acl(17, id)
> Total runtime: 4641.753 ms
> (4 rows)
>
>
>
> What can I do to improve the performance?
Have you tried 'select count (1)..."?
Reinoud
--
__________________________________________________
"Nothing is as subjective as reality"
Reinoud van Leeuwen reinoud.v@n.leeuwen.net
http://reinoud.van.leeuwen.net kvk 27320762
__________________________________________________
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To: pgsql-sql@postgresql.org
Cc: reinoud.v@n.leeuwen.net
Subject: Re: Question on COUNT performance
In-Reply-To: <20100714123029.GH62243@spoetnik.xs4all.nl>
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