From: Bruno Wolff III <bruno@wolff.to>
To: Laurent Manchon <lmanchon@univ-montp2.fr>
Cc: pgsql-performance@postgresql.org
Subject: Re: slow result
Date: Tue, 23 Jan 2007 11:59:51 -0600
Message-ID: <20070123175951.GC20870@wolff.to> (raw)
In-Reply-To: <5.0.2.1.2.20070123113422.00d189e8@pop.univ-montp2.fr>
References: <5.0.2.1.2.20070123113422.00d189e8@pop.univ-montp2.fr>
On Tue, Jan 23, 2007 at 11:34:52 +0100,
Laurent Manchon <lmanchon@univ-montp2.fr> wrote:
> Hi,
>
> I have a slow response of my PostgreSQL database 7.4 using this query below
> on a table with 800000 rows:
>
> select count(*)from tbl;
>
> PostgreSQL return result in 28 sec every time.
> although MS-SQL return result in 0.02 sec every time.
Besides the other advice mentioned in this thread, check that you don't
have a lot of dead tuples in that table. 28 seconds seems a bit high
for even a sequential scan of 800000 tuples unless they are pretty large.
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To: pgsql-performance@postgresql.org
Cc: bruno@wolff.to, lmanchon@univ-montp2.fr
Subject: Re: slow result
In-Reply-To: <20070123175951.GC20870@wolff.to>
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