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To: David Fetter <david@fetter.org>
Cc: PostgreSQL Docs <pgsql-docs@postgresql.org>,
	PostgreSQL Patches <pgsql-patches@postgresql.org>
Subject: Re: Approximate count(*) 
In-reply-to: <20050324170137.GA15848@fetter.org> 
References: <20050324170137.GA15848@fetter.org>
Comments: In-reply-to David Fetter <david@fetter.org>
	message dated "Thu, 24 Mar 2005 09:01:37 -0800"
Date: Thu, 24 Mar 2005 12:34:51 -0500
Message-ID: <27948.1111685691@sss.pgh.pa.us>
From: Tom Lane <tgl@sss.pgh.pa.us>
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David Fetter <david@fetter.org> writes:
> Please find enclosed a patch that shows how to get a quick
> approximation of count(*) on a table.

I'm not sure we should be encouraging people to look at reltuples...
for one thing, it's deliberately a moving average under 8.0.

			regards, tom lane