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From: Tom Lane <tgl@sss.pgh.pa.us>
To: Marc-Olaf Jaschke <moj@dshare.de>
cc: pgsql-hackers@lists.postgresql.org
Subject: Re: Improve hash join's handling of tuples with null join keys
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Comments: In-reply-to Marc-Olaf Jaschke <moj@dshare.de>
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Marc-Olaf Jaschke <moj@dshare.de> writes:
> I can confirm that the patch fixes the issue (Bug #19030). The memory us=
age 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