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From: Tom Lane <tgl@sss.pgh.pa.us>
To: Florian Lohoff <f@zz.de>
cc: pgsql-performance@postgresql.org
Subject: Re: union all and filter / index scan -> seq scan
In-reply-to: <20150521104103.GB10049@pax.zz.de>
References: <20150521104103.GB10049@pax.zz.de>
Comments: In-reply-to Florian Lohoff <f@zz.de>
 message dated "Thu, 21 May 2015 12:41:03 +0200"
Date: Thu, 21 May 2015 11:28:16 -0400
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Florian Lohoff <f@zz.de> writes:
> It seems the planner is not able to rewrite a union all

I do not see any problems with pushing indexable conditions down through a
UNION ALL when I try it.  I speculate that either you are using a very old
9.1.x minor release, or the actual view is more complex than you've let on.

			regards, tom lane


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