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From: Tom Lane <tgl@sss.pgh.pa.us>
To: Tomas Vondra <tomas.vondra@2ndquadrant.com>
cc: David Rowley <dgrowleyml@gmail.com>,
 PostgreSQL-development <pgsql-hackers@postgresql.org>
Subject: Re: Performance improvement for joins where outer side is unique
In-reply-to: <54EF4B80.7020902@2ndquadrant.com>
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Comments: In-reply-to Tomas Vondra <tomas.vondra@2ndquadrant.com>
 message dated "Thu, 26 Feb 2015 17:36:16 +0100"
Date: Thu, 26 Feb 2015 12:34:24 -0500
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Tomas Vondra <tomas.vondra@2ndquadrant.com> writes:
> FWIW this apparently happens because the code only expect that
> EquivalenceMembers only contain Var, but in this particular case that's
> not the case - it contains RelabelType (because oprcode is regproc, and
> needs to be relabeled to oid).

If it thinks an EquivalenceMember must be a Var, it's outright broken;
I'm pretty sure any nonvolatile expression is possible.

			regards, tom lane


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