Message-ID: <cea712ca-d5db-432e-9170-bcb1ed3b95ee@gmail.com>
Date: Fri, 22 Nov 2024 15:39:02 +0700
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Subject: Re: Reordering DISTINCT keys to match input path's pathkeys
To: Richard Guo <guofenglinux@gmail.com>
Cc: PostgreSQL-development <pgsql-hackers@postgresql.org>,
 David Rowley <dgrowleyml@gmail.com>
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From: Andrei Lepikhov <lepihov@gmail.com>
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On 11/13/24 13:49, Richard Guo wrote:
> On Mon, Oct 28, 2024 at 6:15 PM Andrei Lepikhov <lepihov@gmail.com> wrote:
>> On 6/7/24 16:46, Richard Guo wrote:
> I'm not sure about merging these two 'reordering' GUCs into one.
> While they may look similar, they apply to very different scenarios.
> However, I'm open to other suggestions.
I finally have passed through the code. It generally looks OK. Let me 
only write a few words on tests.
I wonder if it would be possible to print only three rows instead of 10 
to prove the DISTINCT's correctness.
Also, to stabilise tests with parallel workers, I would recommend 
setting max_parallel_workers_per_gather into 1 and enabling 
debug_parallel_query.

-- 
regards, Andrei Lepikhov