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Re: index scan cost

From: Jeff Frost <jeff(at)frostconsultingllc(dot)com>
To: Dennis Brakhane <brakhane(at)googlemail(dot)com>
Cc: pgsql-performance(at)postgresql(dot)org
Subject: Re: index scan cost
Date: 2008-07-17 23:12:44
Message-ID: Pine.LNX.4.64.0807171611510.4738@discord.home.frostconsultingllc.com (view raw or flat)
Thread:
Lists: pgsql-performance
On Fri, 18 Jul 2008, Dennis Brakhane wrote:

> The "fast" server makes a much more accurate estimation of the number
> of rows to expect (4 rows are returning, 1 was estimated). The "slow"
> server estimates 1151 rows. Try running ANALYZE on the slow one

You're quite right.  I probably didn't mention that the slow one has been 
analyzed several times.  In fact, every time adjusted the statistics target 
for that column I analyzed, thus the eventually better, but still inaccurate 
estimates toward the bottom of the post.

-- 
Jeff Frost, Owner 	<jeff(at)frostconsultingllc(dot)com>
Frost Consulting, LLC 	http://www.frostconsultingllc.com/
Phone: 650-780-7908	FAX: 650-649-1954

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