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To: Craig James <craig_james@emolecules.com>
cc: pgsql-performance@postgresql.org
Subject: Re: Query on view radically slower than query on underlying table 
In-reply-to: <4D6BE95C.3090102@emolecules.com> 
References: <201102281038.04945.cousinmarc@gmail.com>
	<4D6B9BC9.1000404@enterprisedb.com>
	<4D6BE95C.3090102@emolecules.com>
Comments: In-reply-to Craig James <craig_james@emolecules.com>
	message dated "Mon, 28 Feb 2011 10:28:44 -0800"
Date: Mon, 28 Feb 2011 13:57:36 -0500
Message-ID: <27415.1298919456@sss.pgh.pa.us>
From: Tom Lane <tgl@sss.pgh.pa.us>
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Craig James <craig_james@emolecules.com> writes:
> My guess (and it's just a wild guess) is that the "left join" is
> forcing a sequence scan or something.

No, that's forcing the other join to be done in toto because it can't
reorder the left join and regular join.

			regards, tom lane