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Message-ID: <435C801F.1030709@openwide.fr>
Date: Mon, 24 Oct 2005 08:33:03 +0200
From: Guillaume Smet <guillaume.smet@openwide.fr>
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To: "Steinar H. Gunderson" <sgunderson@bigfoot.com>
Cc: pgsql-performance@postgresql.org
Subject: Re: Problem analyzing explain analyze output
References: <435C2297.5050207@openwide.fr>
	<20051024000824.GA11800@samfundet.no>
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Steinar,

> which seems to make sense; you have one run of about 257ms, plus 514 runs
> taking about 0.035ms each (ie. about 18ms), which should add up to become
> about 275ms (which is close enough to the reality of 281ms).

Yep. The line that disturbed me was the bitmap index scan with a cost of 
"actual time=254.143..254.143". I was more looking for something like 
"actual time=0..254.143" which is what I usually have for an index scan. 
So I suppose that the bitmap index scan returns rows only when it's 
totally computed.

Thanks for your help.

Regards.

--
Guillaume