Received: from malur.postgresql.org ([217.196.149.56]) by arkaria.postgresql.org with esmtps (TLS1.3:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1mzoEh-0005jm-BI for pgsql-performance@arkaria.postgresql.org; Tue, 21 Dec 2021 23:07:59 +0000 Received: from localhost ([127.0.0.1] helo=malur.postgresql.org) by malur.postgresql.org with esmtp (Exim 4.92) (envelope-from ) id 1mzoEg-0003Wv-6u for pgsql-performance@arkaria.postgresql.org; Tue, 21 Dec 2021 23:07:58 +0000 Received: from magus.postgresql.org ([2a02:c0:301:0:ffff::29]) by malur.postgresql.org with esmtps (TLS1.3:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1mzoEf-0003Wf-TR for pgsql-performance@lists.postgresql.org; Tue, 21 Dec 2021 23:07:57 +0000 Received: from sss.pgh.pa.us ([66.207.139.130]) by magus.postgresql.org with esmtps (TLS1.3:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.92) (envelope-from ) id 1mzoEd-0002l9-Fs for pgsql-performance@lists.postgresql.org; Tue, 21 Dec 2021 23:07:57 +0000 Received: from sss1.sss.pgh.pa.us (localhost [127.0.0.1]) by sss.pgh.pa.us (8.15.2/8.15.2) with ESMTP id 1BLN7qRM166330; Tue, 21 Dec 2021 18:07:52 -0500 From: Tom Lane To: Lars Bergeson cc: Justin Pryzby , "David G. Johnston" , pgsql-performance@lists.postgresql.org Subject: Re: Query is slower with a large proportion of NULLs in several columns In-reply-to: References: <2688019.1640051519@sss.pgh.pa.us> <20211221045138.GZ17618@telsasoft.com> <2704544.1640062888@sss.pgh.pa.us> <2707817.1640064786@sss.pgh.pa.us> <20211221211337.GB17618@telsasoft.com> Comments: In-reply-to Lars Bergeson message dated "Tue, 21 Dec 2021 14:53:20 -0800" MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-ID: <166328.1640128072.1@sss.pgh.pa.us> Date: Tue, 21 Dec 2021 18:07:52 -0500 Message-ID: <166329.1640128072@sss.pgh.pa.us> List-Id: List-Help: List-Subscribe: List-Post: List-Owner: List-Archive: Archived-At: Precedence: bulk Lars Bergeson writes: > I'm running PostgreSQL under AWS Aurora, and I didn't set it up or install > it, so I'm not sure about the OS version. Oh! Aurora is not Postgres. My admittedly-not-well-informed understanding is that they stuck a Postgres front end on their existing storage engine, so it's not surprising if storage-level behaviors are quite different from stock Postgres. regards, tom lane