From: Andrew Dunstan <andrew@dunslane.net>
To: pgsql-perform <pgsql-performance@postgresql.org>
Subject: encouraging index-only scans
Date: Wed, 12 Dec 2012 16:06:52 -0500
Message-ID: <50C8F1EC.9010801@dunslane.net> (raw)
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A client is testing a migration from 9.1 to 9.2, and has found that a
large number of queries run much faster if they use index-only scans.
However, the only way he has found to get such a plan is by increasing
the seq_page_cost to insanely high levels (3.5). Is there any approved
way to encourage such scans that's a but less violent than this?
cheers
andrew
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To: pgsql-performance@postgresql.org
Cc: andrew@dunslane.net
Subject: Re: encouraging index-only scans
In-Reply-To: <50C8F1EC.9010801@dunslane.net>
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