Date: Thu, 24 Nov 2005 22:24:35 +1300
From: Mark Kirkwood <markir@paradise.net.nz>
Subject: Re: Hardware/OS recommendations for large databases (
In-reply-to: <BFAAB702.1460D%llonergan@greenplum.com>
To: Luke Lonergan <llonergan@greenplum.com>
Cc: stange@rentec.com, Greg Stark <gsstark@mit.edu>,
	Dave Cramer <pg@fastcrypt.com>, Joshua Marsh <icub3d@gmail.com>,
	pgsql-performance@postgresql.org
Message-id: <438586D3.9010701@paradise.net.nz>
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References: <BFAAB702.1460D%llonergan@greenplum.com>

Luke Lonergan wrote:

> That says it's something else in the path.  As you probably know there is a
> page lock taken, a copy of the tuple from the page, lock removed, count
> incremented for every iteration of the agg node on a count(*).  Is the same
> true of a count(1)?
> 

Sorry Luke - message 3 - I seem to be suffering from a very small 
working memory buffer myself right now, I think it's after a day of 
working with DB2 ... :-)

Anyway, as I read src/backend/parser/gram.y:6542 - count(*) is 
transformed into count(1), so these two are identical.

Cheers (last time tonight, promise!)

Mark