Re: Memoize ANTI and SEMI JOIN inner

Richard Guo <guofenglinux@gmail.com>

From: Richard Guo <guofenglinux@gmail.com>

To: David Rowley <dgrowleyml@gmail.com>

Cc: Andrei Lepikhov <lepihov@gmail.com>, PostgreSQL-development <pgsql-hackers@postgresql.org>

Date: 2025-04-10T10:36:14Z

Lists: pgsql-hackers

Commits

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Enable use of Memoize for ANTI joins
- 0da29e4cb161 19 (unreleased) landed

Attachments

v1-0001-Enable-use-of-Memoize-for-ANTI-joins.patch (application/octet-stream) patch v1-0001

On Wed, Apr 9, 2025 at 6:18 PM David Rowley <dgrowleyml@gmail.com> wrote:
> On Wed, 9 Apr 2025 at 18:48, Richard Guo <guofenglinux@gmail.com> wrote:
> > Perhaps we could spend some planner cycles proving inner_unique for
> > anti joins, so that Memoize nodes can be considered for them?

> Worth a try. It should be pretty easy to enable, as far as I can see.
> It might just be a case of shuffling the cases around in the switch
> statement in add_paths_to_joinrel().

Right.  Here is a patch for that.

Thanks
Richard