Received: from malur.postgresql.org ([217.196.149.56]) by arkaria.postgresql.org with esmtps (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.96) (envelope-from ) id 1vQ6EA-00A0zW-06 for pgsql-bugs@arkaria.postgresql.org; Mon, 01 Dec 2025 15:54:14 +0000 Received: from localhost ([127.0.0.1] helo=malur.postgresql.org) by malur.postgresql.org with esmtp (Exim 4.96) (envelope-from ) id 1vQ6E8-003So3-1X for pgsql-bugs@arkaria.postgresql.org; Mon, 01 Dec 2025 15:54:12 +0000 Received: from makus.postgresql.org ([2001:4800:3e1:1::229]) by malur.postgresql.org with esmtps (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.96) (envelope-from ) id 1vQ6E8-003Snv-0g for pgsql-bugs@lists.postgresql.org; Mon, 01 Dec 2025 15:54:12 +0000 Received: from sss.pgh.pa.us ([68.162.161.243]) by makus.postgresql.org with esmtps (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.96) (envelope-from ) id 1vQ6E6-002b2V-04 for pgsql-bugs@lists.postgresql.org; Mon, 01 Dec 2025 15:54:11 +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 5B1Fs9jI192742; Mon, 1 Dec 2025 10:54:09 -0500 From: Tom Lane To: d.kovalenko@postgrespro.ru cc: pgsql-bugs@lists.postgresql.org Subject: Re: BUG #19338: [PG15] Unstable SQL result in test regress/tablespace In-reply-to: <19338-3dd4f9982d9b55a9@postgresql.org> References: <19338-3dd4f9982d9b55a9@postgresql.org> Comments: In-reply-to PG Bug reporting form message dated "Mon, 01 Dec 2025 11:31:19 +0000" MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-ID: <192740.1764604449.1@sss.pgh.pa.us> Date: Mon, 01 Dec 2025 10:54:09 -0500 Message-ID: <192741.1764604449@sss.pgh.pa.us> List-Id: List-Help: List-Subscribe: List-Post: List-Owner: List-Archive: Archived-At: Precedence: bulk PG Bug reporting form writes: > PG15 has an unstable SQL in test regress/tablespace: I tried to reproduce this, without much success. For me, that query gives the same EXPLAIN plan and the same results with or without ORDER BY. (It chooses an indexscan that'd naturally order the results.) And the v15 regression tests pass fine in a few different locales I tried, which doesn't surprise me given the lack of prior complaints. In short, I think there's more going on here than meets the eye. Can you give a recipe for reproducing this failure? regards, tom lane