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	Thu, 8 Jun 2017 13:50:57 -0400
From: Tom Lane <tgl@sss.pgh.pa.us>
To: "'Andres Freund'" <andres@anarazel.de>
cc: Regina Obe <lr@pcorp.us>, "'Mark Dilger'" <hornschnorter@gmail.com>,
        "'PostgreSQL-development'" <pgsql-hackers@postgresql.org>
Subject: Re: PostgreSQL 10 changes in exclusion constraints - did something
 change? CASE WHEN behavior oddity
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Comments: In-reply-to "'Andres Freund'" <andres@anarazel.de>
	message dated "Thu, 08 Jun 2017 10:07:22 -0700"
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Date: Thu, 08 Jun 2017 13:50:57 -0400
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"'Andres Freund'" <andres@anarazel.de> writes:
> On 2017-06-08 11:57:49 -0400, Regina Obe wrote:
>> My main concern in these cases is the short-circuiting not happening.

> Note there's also no short-circuiting e.g. for aggregates inside case
> either.

Well, depends.  If const-folding manages to get rid of the aggregate
call altogether, it won't be computed.

			regards, tom lane


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