From: Bruno Wolff III <bruno@wolff.to>
To: Nikola Ivacic <nikola@rs-pi.com>
Cc: pgsql-sql@postgresql.org
Subject: Re: count(*) optimization
Date: Wed, 8 Jan 2003 10:22:58 -0600
Message-ID: <20030108162258.GA9033@wolff.to> (raw)
In-Reply-To: <024d01c2b72f$a6a7dcc0$1100a8c0@rspi>
References: <024d01c2b72f$a6a7dcc0$1100a8c0@rspi>
On Wed, Jan 08, 2003 at 17:04:40 +0100,
Nikola Ivacic <nikola@rs-pi.com> wrote:
> Hi
>
> I have trouble executing count(*) statement.
> On a large dataset it takes quite a while to return result.
> Is there any other way to get number of tupples in relation
> or is the only way to optimize count() function to index it?
Indexes won't help count.
If you retrieve counts a lot more than you do updates that will change their
value, then you may want to keep the counts in another table and use
triggers to keep them updated.
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To: pgsql-sql@postgresql.org
Cc: bruno@wolff.to, nikola@rs-pi.com
Subject: Re: count(*) optimization
In-Reply-To: <20030108162258.GA9033@wolff.to>
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