Re: A problem in deconstruct_distribute_oj_quals - Mailing list pgsql-hackers

From Tom Lane
Subject Re: A problem in deconstruct_distribute_oj_quals
Date
Msg-id 3200967.1675789104@sss.pgh.pa.us
Whole thread Raw
In response to Re: A problem in deconstruct_distribute_oj_quals  (Richard Guo <guofenglinux@gmail.com>)
List pgsql-hackers
Richard Guo <guofenglinux@gmail.com> writes:
> On Tue, Feb 7, 2023 at 2:12 PM Tom Lane <tgl@sss.pgh.pa.us> wrote:
>> I don't see any change in this query plan when I remove that code, so
>> I'm not sure you're explaining your point very well.

> To observe an obvious plan change, we can add unique constraint for 'a'
> and look how outer-join removal works.

Ah.  Yeah, that's pretty convincing, especially since v15 manages to
find that optimization.  Pushed with a test case.

            regards, tom lane



pgsql-hackers by date:

Previous
From: Robert Haas
Date:
Subject: Re: run pgindent on a regular basis / scripted manner
Next
From: Paul Ramsey
Date:
Subject: Re: daitch_mokotoff module