Received: from malur.postgresql.org ([217.196.149.56]) by arkaria.postgresql.org with esmtp (Exim 4.80) (envelope-from ) id 1XSGrO-0003Ee-31 for pgsql-performance@arkaria.postgresql.org; Fri, 12 Sep 2014 02:45:18 +0000 Received: from localhost ([127.0.0.1] helo=postgresql.org) by malur.postgresql.org with smtp (Exim 4.80) (envelope-from ) id 1XSGrN-000534-EP for pgsql-performance@arkaria.postgresql.org; Fri, 12 Sep 2014 02:45:17 +0000 Received: from makus.postgresql.org ([2001:4800:1501:1::229]) by malur.postgresql.org with esmtps (TLS1.2:DHE_RSA_AES_256_CBC_SHA256:256) (Exim 4.80) (envelope-from ) id 1XSGrM-00052a-JP for pgsql-performance@postgresql.org; Fri, 12 Sep 2014 02:45:16 +0000 Received: from sam.nabble.com ([216.139.236.26]) by makus.postgresql.org with esmtps (TLS1.0:RSA_AES_256_CBC_SHA1:256) (Exim 4.80) (envelope-from ) id 1XSGrC-0001U2-PW for pgsql-performance@postgresql.org; Fri, 12 Sep 2014 02:45:14 +0000 Received: from [192.168.236.26] (helo=sam.nabble.com) by sam.nabble.com with esmtp (Exim 4.72) (envelope-from ) id 1XSGrB-0002Za-CE for pgsql-performance@postgresql.org; Thu, 11 Sep 2014 19:45:05 -0700 Date: Thu, 11 Sep 2014 19:45:05 -0700 (PDT) From: David G Johnston To: pgsql-performance@postgresql.org Message-ID: <1410489905373-5818733.post@n5.nabble.com> In-Reply-To: References: Subject: Re: weird execution plan MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit X-Pg-Spam-Score: 0.8 (/) List-Archive: List-Help: List-ID: List-Owner: List-Post: List-Subscribe: List-Unsubscribe: X-Mailing-List: pgsql-performance Precedence: bulk Sender: pgsql-performance-owner@postgresql.org Huang, Suya wrote > Can someone figure out why the first query runs so slow comparing to the > second one? They generate the same result... Try: EXPLAIN (ANALYZE, BUFFERS) I believe you are only seeing caching effects. David J. -- View this message in context: http://postgresql.1045698.n5.nabble.com/weird-execution-plan-tp5818730p5818733.html Sent from the PostgreSQL - performance mailing list archive at Nabble.com. -- Sent via pgsql-performance mailing list (pgsql-performance@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-performance