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From: David Rowley <dgrowleyml@gmail.com>
Date: Mon, 30 May 2022 14:51:16 +1200
Message-ID: 
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Subject: Re: BUG #17502: View based on window functions returns wrong results
 when queried
To: Tom Lane <tgl@sss.pgh.pa.us>
Cc: =?UTF-8?Q?Daniel_Farka=C5=A1?= <daniel.farkas@datoris.com>,
	Magnus Hagander <magnus@hagander.net>,
	PostgreSQL mailing lists <pgsql-bugs@lists.postgresql.org>
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On Mon, 30 May 2022 at 14:45, Tom Lane <tgl@sss.pgh.pa.us> wrote:
>
> David Rowley <dgrowleyml@gmail.com> writes:
> > On Mon, 30 May 2022 at 14:19, Tom Lane <tgl@sss.pgh.pa.us> wrote:
> >> I was sort of wondering why we allow SRFs in this context in the
> >> first place.  The results don't seem terribly well-defined to me.
>
> > Do you think it would fly to add such a restriction in the backbranches?
>
> We could leave it alone in the back branches on the grounds that if
> you like the results you get, we shouldn't break it in a minor
> release.

I struggle to see how anyone would like their result correctness to
depend on whether remove_unused_subquery_outputs() is able or unable
to remove a column from the subquery.

David