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To: Robert Haas <robertmhaas@gmail.com>
cc: =?ISO-8859-1?Q?C=E9dric_Villemain?= <cedric.villemain.debian@gmail.com>,
	panam <panam@gmx.net>,
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Subject: Re: [PERFORM] Hash Anti Join performance degradation 
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Comments: In-reply-to Robert Haas <robertmhaas@gmail.com>
	message dated "Wed, 01 Jun 2011 16:43:29 -0400"
Date: Wed, 01 Jun 2011 16:47:36 -0400
Message-ID: <24707.1306961256@sss.pgh.pa.us>
From: Tom Lane <tgl@sss.pgh.pa.us>
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Robert Haas <robertmhaas@gmail.com> writes:
> I guess the real issue here is that m1.id < m2.id has to be evaluated
> as a filter condition rather than a join qual.

Well, if you can invent an optimized join technique that works for
inequalities, go for it ... but I think you should get at least a
PhD thesis out of that.

			regards, tom lane