Re: Improve hash join's handling of tuples with null join keys

Tom Lane <tgl@sss.pgh.pa.us>

From: Tom Lane <tgl@sss.pgh.pa.us>
To: Marc-Olaf Jaschke <moj@dshare.de>
Cc: pgsql-hackers@lists.postgresql.org
Date: 2025-08-24T19:18:33Z
Lists: pgsql-hackers
Marc-Olaf Jaschke <moj@dshare.de> writes:
> I can confirm that the patch fixes the issue (Bug #19030). The memory usage remains within the expected range of work_mem.
> This also applies to parallel hash joins.
> The query also runs significantly faster.
> I also tested cases with multiple left joins.
> I have only observed this problem when there are many null values in the join column.

Thanks for testing!

			regards, tom lane



Commits

  1. Improve hash join's handling of tuples with null join keys.