From: Tom Lane <tgl@sss.pgh.pa.us>
To: David Rowley <dgrowleyml@gmail.com>
cc: PostgreSQL Developers <pgsql-hackers@lists.postgresql.org>
Subject: Re: Buglets in equivclass.c
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Comments: In-reply-to David Rowley <dgrowleyml@gmail.com>
	message dated "Mon, 05 Oct 2020 10:11:04 +1300"
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Date: Mon, 05 Oct 2020 13:17:27 -0400
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David Rowley <dgrowleyml@gmail.com> writes:
> On Mon, 5 Oct 2020 at 06:29, Tom Lane <tgl@sss.pgh.pa.us> wrote:
>> I'm unsure whether to back-patch either of these.  They both seem to be
>> just latent bugs so far as the core code is concerned, but the first one
>> in particular seems like something that could bite extension code.
>> Thoughts?

> That's a good question. I'm leaning towards backpatching both of them.
> The 2nd is new as of v13, so it does not seem unreasonable that
> someone has just not yet stumbled on it with some extension that adds
> extra child ECs. I can imagine a use case for that, by getting rid of
> needless equality quals that duplicate the partition constraint.  The
> fix for the first just seems neater/faster/correct, so I can't really
> see any reason not to backpatch it.

Yeah, that's my conclusion too after sleeping on it.  Pushed,
thanks for reviewing.

			regards, tom lane