Message-ID: <5C876354.1000905@lab.ntt.co.jp>
Date: Tue, 12 Mar 2019 16:44:20 +0900
From: Etsuro Fujita <fujita.etsuro@lab.ntt.co.jp>
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Subject: Re: Oddity with parallel safety test for scan/join target in
 grouping_planner
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 <5C85DC65.2050409@lab.ntt.co.jp> <32401.1552277190@sss.pgh.pa.us>
 <5C85ED63.8000805@lab.ntt.co.jp> <1962.1552281261@sss.pgh.pa.us>
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To: Tom Lane <tgl@sss.pgh.pa.us>
Cc: Robert Haas <robertmhaas@gmail.com>,
        Pg Hackers <pgsql-hackers@postgresql.org>
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(2019/03/11 23:46), Tom Lane wrote:
> So this is
> just a plan-quality problem not a wrong-answer problem.
>
> However, I'd still argue for back-patching into v11, on the grounds
> that this is a regression from v10.  The example you just gave does
> produce the desired plan in v10, and I think it's more likely that
> people would complain about a regression from v10 than that they'd
> be unhappy because we changed it between 11.2 and 11.3.

Agreed.  I committed the patch to v11 and HEAD.  Thanks for reviewing!

Best regards,
Etsuro Fujita