Message-ID: <379609b13ed86654d40521eca5dd7984a238a1c7.camel@postgrespro.ru>
Subject: Re: Fix BUG #17335: Duplicate result rows in Gather node
From: Yura Sokolov <y.sokolov@postgrespro.ru>
To: David Rowley <dgrowleyml@gmail.com>
Cc: PostgreSQL Developers <pgsql-hackers@lists.postgresql.org>
Date: Tue, 25 Jan 2022 12:29:07 +0300
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В Вт, 25/01/2022 в 21:20 +1300, David Rowley пишет:
> On Tue, 25 Jan 2022 at 20:03, David Rowley <dgrowleyml@gmail.com> wrote:
> > On Tue, 25 Jan 2022 at 17:35, Yura Sokolov <y.sokolov@postgrespro.ru> wrote:
> > > And another attempt to fix tests volatility.
> > 
> > FWIW, I had not really seen the point in adding a test for this.   I
> > did however see a point in it with your original patch. It seemed
> > useful there to verify that Gather and GatherMerge did what we
> > expected with 1 worker.
> 
> I ended up pushing just the last patch I sent.
> 
> The reason I didn't think it was worth adding a new test was that no
> tests were added in the original commit.  Existing tests did cover it,

Existed tests didn't catched the issue. It is pitty fix is merged
without test case it fixes.

> but here we're just restoring the original behaviour for one simple
> case.  The test in your patch just seemed a bit more hassle than it
> was worth. I struggle to imagine how we'll break this again.

Thank you for attention and for fix.

regards,
Yura Sokolov.