Re: apply_scanjoin_target_to_paths and partitionwise join

From: Robert Haas <robertmhaas(at)gmail(dot)com>
To: Ashutosh Bapat <ashutosh(dot)bapat(dot)oss(at)gmail(dot)com>
Cc: Richard Guo <guofenglinux(at)gmail(dot)com>, Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>, Andrei Lepikhov <lepihov(at)gmail(dot)com>, Jakub Wartak <jakub(dot)wartak(at)enterprisedb(dot)com>, arne(dot)roland(at)malkut(dot)net, PostgreSQL Hackers <pgsql-hackers(at)lists(dot)postgresql(dot)org>, Julien Rouhaud <rjuju123(at)gmail(dot)com>, Etsuro Fujita <etsuro(dot)fujita(at)gmail(dot)com>
Subject: Re: apply_scanjoin_target_to_paths and partitionwise join
Date: 2025-12-24 13:28:23
Message-ID: CA+TgmoYhUtGLx6phmxNMo0bsOMJabiOzNTJEmAma7se=H89GcA@mail.gmail.com
Views: Whole Thread | Raw Message | Download mbox | Resend email
Thread:
Lists: pgsql-hackers

Thanks for writing back. I only just noticed this thread again.

On Wed, Dec 17, 2025 at 5:53 AM Ashutosh Bapat
<ashutosh(dot)bapat(dot)oss(at)gmail(dot)com> wrote:
> My patch removed a redundant SET enable_partitionwise_join = on. That
> change is not included in your commit, I believe, because it's
> irrelevant to the fix. However, it's better to avoid the redundancy to
> avoid confusion. PFA patch for the same.

Yeah, I couldn't really understand your test case changes, so I
basically redid those from scratch. I personally think that the
regression tests are kind of horrible about how they use SET enable_*
commands. It's often extremely difficult to figure out what the
current values are at any given point in what may be a very long test
case file. I don't have an opinion at the present time on whether
changing this makes it more or less confusing.

> [3] https://www.postgresql.org/message-id/786.1565541557%40sss.pgh.pa.us

This is a really interesting link. Your email contained no reference
to this footnote (unless I missed something) but it seems quite
relevant to this discussion.

--
Robert Haas
EDB: http://www.enterprisedb.com

In response to

Responses

Browse pgsql-hackers by date

  From Date Subject
Next Message Robert Haas 2025-12-24 13:32:42 Re: should we have a fast-path planning for OLTP starjoins?
Previous Message Jelte Fennema-Nio 2025-12-24 13:28:19 cleanup: Split long Makefile lists across lines and sort them