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Date: Wed, 8 Jan 2003 10:22:58 -0600
From: Bruno Wolff III <bruno@wolff.to>
To: Nikola Ivacic <nikola@rs-pi.com>
Cc: pgsql-sql@postgresql.org
Subject: Re: count(*) optimization
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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.