From: A. Kretschmer <andreas.kretschmer@schollglas.com>
To: pgsql-sql@postgresql.org
Subject: Re: slow query
Date: Thu, 5 Apr 2007 07:36:38 +0200
Message-ID: <20070405053637.GC24814@a-kretschmer.de> (raw)
In-Reply-To: <19157.1175750845@sss.pgh.pa.us>
References: <7539aebb0704042017l70d83d53u9c2e5105620a3fa7@mail.gmail.com>
<20070405051127.GA24814@a-kretschmer.de>
<19157.1175750845@sss.pgh.pa.us>
am Thu, dem 05.04.2007, um 1:27:25 -0400 mailte Tom Lane folgendes:
> "A. Kretschmer" <andreas.kretschmer@schollglas.com> writes:
> > am Wed, dem 04.04.2007, um 23:17:54 -0400 mailte Sumeet folgendes:
> >> sm=> explain analyze select * from ma limit 10;
> >> QUERY
> >> PLAN
> >> -------------------------------------------------------------------------------------------------------------------------------------
> >> Limit (cost=0.00..0.45 rows=10 width=76) (actual time=21985.292..22204.340
> >> rows=10 loops=1)
> >> -> Seq Scan on ma (cost=0.00..2181956.92 rows=48235392 width=76) (actual
> >> time=21985.285..22204.308 rows=10 loops=1)
> >> Total runtime: 22204.476 ms
> >> (3 rows)
>
> > which version?
>
> I'm betting the problem is poor vacuuming practice leading to lots of
> dead space. There's no way it takes 22 sec to read 10 rows if the
> table is reasonably dense.
This was my first thought, but:
,----[ Quote ]
| I've tried
| vacuuming this table many time
`----
Andreas
--
Andreas Kretschmer
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To: pgsql-sql@postgresql.org
Cc: andreas.kretschmer@schollglas.com
Subject: Re: slow query
In-Reply-To: <20070405053637.GC24814@a-kretschmer.de>
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