Re: Pathify RHS unique-ification for semijoin planning

Richard Guo <guofenglinux@gmail.com>

From: Richard Guo <guofenglinux@gmail.com>

To: PostgreSQL-development <pgsql-hackers@postgresql.org>, Tom Lane <tgl@sss.pgh.pa.us>

Cc: Andy Fan <zhihuifan1213@163.com>, wenhui qiu <qiuwenhuifx@gmail.com>

Date: 2025-07-16T02:30:35Z

Lists: pgsql-hackers

Commits

Same data as JSON: GET /api/v1/messages/:b64id/commits the thread's linked commits as JSON, with link sources. API reference →

Simplify relation_has_unique_index_for()
- bf9ee294e567 19 (unreleased) landed
Pathify RHS unique-ification for semijoin planning
- 24225ad9aafc 19 (unreleased) landed
Convert varatt.h access macros to static inline functions.
- e035863c9a04 19 (unreleased) cited
Re-export a few of createplan.c's make_xxx() functions.
- 570be1f73f38 9.6.0 cited

Attachments

v5-0001-Pathify-RHS-unique-ification-for-semijoin-plannin.patch (application/octet-stream) patch v5-0001

On Fri, Jul 4, 2025 at 10:41 AM Richard Guo <guofenglinux@gmail.com> wrote:
> On Thu, Jul 3, 2025 at 7:06 PM Richard Guo <guofenglinux@gmail.com> wrote:
> > This patch does not apply again, so here is a new rebase.
> >
> > This version also fixes an issue related to parameterized paths: if
> > the RHS has LATERAL references to the LHS, unique-ification becomes
> > meaningless because the RHS depends on the LHS, and such paths should
> > not be generated.

> (The cc list is somehow lost; re-ccing.)

The CI reports a test failure related to this patch, although I'm
quite confident it's unrelated to the changes introduced here.

The failure is: recovery/009_twophase time out (After 1000 seconds)

In any case, here's a freshly rebased version.

Hi Tom, I wonder if you've had a chance to look at this patch.  It
would be great to have your input.

Thanks
Richard