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Date: Thu, 27 Oct 2011 15:31:00 -0500
From: Shaun Thomas <sthomas@peak6.com>
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To: Robert Haas <robertmhaas@gmail.com>
CC: Giovanni Mancuso <gmancuso@babel.it>, <pgsql-performance@postgresql.org>
Subject: Re: Performance problem with a table with 38928077 record
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On 10/27/2011 02:13 PM, Robert Haas wrote:

> If I had to guess, I'd bet that the second one is trying to spool the
> resultset in memory someplace and that's driving the machine into
> swap.

That would be my guess too. SELECT * on a 40-million row table is a 
*lot* different than getting the count, which throws away the rows once 
it verifies they're valid.

-- 
Shaun Thomas
OptionsHouse | 141 W. Jackson Blvd. | Suite 800 | Chicago IL, 60604
312-676-8870
sthomas@peak6.com

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