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: 2025-07-02T02:08:01Z

Lists: pgsql-hackers

Commits

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

Attachments

v3-0001-Enable-use-of-Memoize-for-ANTI-joins.patch (application/octet-stream) patch v3-0001

On Thu, Apr 10, 2025 at 7:36 PM Richard Guo <guofenglinux@gmail.com> wrote:
> 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.

Here's a rebased version with no other changes.

David, Andrei, would you like to take another look?  I'm planning to
push it soon.

Thanks
Richard