From: Tom Lane <tgl@sss.pgh.pa.us>
To: glynastill@yahoo.co.uk
Cc: pgsql-general@postgresql.org
Subject: Re: Planner picking topsey turvey plan?
Date: Sun, 07 Dec 2008 21:02:11 -0500
Message-ID: <5092.1228701731@sss.pgh.pa.us> (raw)
In-Reply-To: <167634.59714.qm@web23608.mail.ird.yahoo.com>
References: <167634.59714.qm@web23608.mail.ird.yahoo.com>
Glyn Astill <glynastill@yahoo.co.uk> writes:
> Does anyone know how I can change what I'm doing to get pgsql to pick a better plan?
You've provided no evidence that this is a bad plan.
In particular, the plan you seem to think would be better would involve
an estimated 153 iterations of the cost-15071 hash aggregation, which
simple arithmetic shows is more expensive than the plan it did choose.
regards, tom lane
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Subject: Re: Planner picking topsey turvey plan?
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