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To: Alvaro Herrera <alvherre@commandprompt.com>
cc: Steve <cheetah@tanabi.org>, pgsql-patches@postgresql.org
Subject: Re: [HACKERS] choose_bitmap_and again (was Re: [PERFORM] Strangely
	Variable Query Performance)
In-reply-to: <20070416230104.GY5658@alvh.no-ip.org> 
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Comments: In-reply-to Alvaro Herrera <alvherre@commandprompt.com>
	message dated "Mon, 16 Apr 2007 19:01:04 -0400"
Date: Tue, 17 Apr 2007 15:04:57 -0400
Message-ID: <4752.1176836697@sss.pgh.pa.us>
From: Tom Lane <tgl@sss.pgh.pa.us>
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Alvaro Herrera <alvherre@commandprompt.com> writes:
> Steve wrote:
>> So I'd say as far as I can tell with my application and my 
>> dataset, this change is solid and an obvious improvement.

> Maybe it would be interesting to see in detail those cases that got a
> bit slower, to further tweak the heuristic if necessary.  Is the extra
> time, time spent in planning or in execution?

Since there doesn't seem to be vast interest out there in testing this
further, I'm going to go ahead and apply the patch to get it out of my
working directory.  We can always tweak it more later if new info
surfaces.

			regards, tom lane