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Re: How Postgresql Compares... Count(*) and others

From:	Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>
To:	Mark kirkwood <markir(at)slingshot(dot)co(dot)nz>
Cc:	Sean Chittenden <sean-pgsql-general(at)chittenden(dot)org>, pgsql-general(at)postgresql(dot)org
Subject:	Re: How Postgresql Compares... Count(*) and others
Date:	2001-07-22 03:49:41
Message-ID:	499.995773781@sss.pgh.pa.us
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Mark kirkwood <markir(at)slingshot(dot)co(dot)nz> writes:
> I have not tried to see if it makes any difference in Postgresql...

Postgres converts count(*) to count(1) at the grammar stage (cf. gram.y,
about line 4817 in current sources). So if you think you detect any
performance difference, you're surely hallucinating...

regards, tom lane

In response to

How Postgresql Compares... Count(*) and others at 2001-07-22 03:06:52 from Mark kirkwood

Responses

Re: How Postgresql.... Putting Count(*) To Bed (Hopefully) at 2001-07-23 08:24:46 from Mark kirkwood

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