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[148.222.54.38]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384) by 100.99.47.133 (trex/7.1.3); Sun, 24 Aug 2025 13:03:46 +0000 Received: from smtpclient.apple (p200300cd9f11bd001845c3c53448c556.dip0.t-ipconnect.de [IPv6:2003:cd:9f11:bd00:1845:c3c5:3448:c556]) (Authenticated sender: marc-olaf.jaschke@dshare.de) by smtp.hostinger.com (smtp.hostinger.com) with ESMTPSA id 4c8vHz061wz1y1h; Sun, 24 Aug 2025 13:03:42 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=dshare.de; s=hostingermail-a; t=1756040623; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=/L00cB8asjhZQLGCTz3J/HTYRfGuEimN5i3ETmq1Ig4=; b=slL1lCzS9IpcbzXgZKKu9wfDLB9w2p/ywSRJvc0KCTskaIJ0iei14S14w/hYVG+SsFcEZd iToAcqECcJVeJMSOXO3T75eVLNNc7dcJZmCDJM9hUodgVmMLtn1JtBdJWjWkpoJay0aIPz TyrrKd9Hijdn9epjtGuvXzA3dggjahWCMcLXtRbMD51PC5cCBIhKUY3P7ACXrBgtXXSmyc MstvuMAMYBJpsAlyVqseku+UZvrDGAitc1qKTpLPDBaE8zNadvuzr0Ow9juSWH7nuuI6UM 25fJ1E3dmnQV9NQerUoJzhJGTkJq3xEKpP3B1J0tZacgTjcIoZwlXOlL/TJhRg== Content-Type: text/plain; charset=us-ascii Mime-Version: 1.0 (Mac OS X Mail 16.0 \(3826.700.81\)) Subject: Re: Improve hash join's handling of tuples with null join keys From: Marc-Olaf Jaschke In-Reply-To: <52163.1755988628@sss.pgh.pa.us> Cc: pgsql-hackers@lists.postgresql.org Content-Transfer-Encoding: quoted-printable Message-Id: <96AC93D7-9A4E-43EE-9CD9-23E973FE8D40@dshare.de> References: <3061845.1746486714@sss.pgh.pa.us> <496221.1748882849@sss.pgh.pa.us> <175507656113.993.1381684440543440253.pgcf@coridan.postgresql.org> <544D7C83-CECE-44E7-B5D7-530E9318D231@gmail.com> <616751.1755276726@sss.pgh.pa.us> <5C5EE031-F086-4353-A17A-DA563CD24DDD@gmail.com> <463296.1755553046@sss.pgh.pa.us> <659B2B36-C0FE-4642-921D-E7120E838891@gmail.com> <52163.1755988628@sss.pgh.pa.us> To: Tom Lane X-Mailer: Apple Mail (2.3826.700.81) Date: Sun, 24 Aug 2025 13:03:42 +0000 (UTC) X-CM-Analysis: v=2.4 cv=DJTd4DNb c=1 sm=1 tr=0 ts=68ab0daf a=0+D6GGjeqZjh/2vImVLPnA==:617 a=xqWC_Br6kY4A:10 a=kj9zAlcOel0A:10 a=epTmVMiNAAAA:8 a=vnRxVlkn9zcvWZJNgUcA:9 a=CjuIK1q_8ugA:10 a=zZCYzV9kfG8A:10 a=ADiJHLWpjGBBXEl7-v_j:22 X-CM-Envelope: MS4xfLh0tF7MP1U2gYPT19nWY65KlgXhyB/ObWfOTM3jRP4JQYDV4ZbwdqEWS7c32ZPhenNMwZTNSGKxFV/FwBid0b9ya0E8ltZ6TqV8XyMjU9e9Sl/fJIAu gT09n3hkIcpb1E3EXhVnmMhuPvG66bTOdOthxqb9zf5Ao+zvaWP/ibJbIfBHTZYTsNX02RQinC3rEkcGyyoJ80O0yAME5MmqBa0Tyg6b4Y51YmWwVSdFx5Zq WYv6MYRmsnfpE8pDsGkAy+ErpDLLi21DEo1wRwSGlCF8hWoHHKFvo8M31yRe6fHw X-AuthUser: marc-olaf.jaschke@dshare.de List-Id: List-Help: List-Subscribe: List-Post: List-Owner: List-Archive: Archived-At: Precedence: bulk Tom Lane wrote: > Bug #19030 [1] seems to be a fresh report of the problem this patch > aims to solve. =20 > [1] = https://www.postgresql.org/message-id/flat/19030-944dd78d7ef94c0f%40postgr= esql.org >=20 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. regards Marc-Olaf Jaschke=