Received: from malur.postgresql.org ([217.196.149.56]) by arkaria.postgresql.org with esmtp (Exim 4.80) (envelope-from ) id 1a1zBV-00076y-5g for pgsql-performance@arkaria.postgresql.org; Thu, 26 Nov 2015 16:14:13 +0000 Received: from localhost ([127.0.0.1] helo=postgresql.org) by malur.postgresql.org with smtp (Exim 4.84) (envelope-from ) id 1a1zBU-0005e4-Lf for pgsql-performance@arkaria.postgresql.org; Thu, 26 Nov 2015 16:14:12 +0000 Received: from magus.postgresql.org ([2a02:c0:301:0:ffff::29]) by malur.postgresql.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_CBC_SHA384:256) (Exim 4.84) (envelope-from ) id 1a1z9r-0003nB-8x for pgsql-performance@postgresql.org; Thu, 26 Nov 2015 16:12:31 +0000 Received: from nm24-vm9.bullet.mail.ir2.yahoo.com ([212.82.97.33]) by magus.postgresql.org with esmtps (TLS1.0:ECDHE_RSA_AES_256_CBC_SHA1:256) (Exim 4.84) (envelope-from ) id 1a1z9n-0000bi-Nl for pgsql-performance@postgresql.org; Thu, 26 Nov 2015 16:12:30 +0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=yahoo.co.uk; s=s2048; t=1448554344; bh=K7YFLx7H+OwYS/heiEKQGxL4HHXRYGfWnwWi7eQ1aXc=; h=Date:From:Reply-To:To:Subject:References:From:Subject; b=FjnkT4w4icl2ANxuNWLKKlt2HFPImbPpz3CNIwureJfdC3GKqkCNyV+UPho+UwvmCRh7hwCSCWj5ZxLqpmMHsEcjO4Qi0NyDqU71PxN8+fy5dAgmqENH7/IDLPPtNCSb01DQ/ZsPqecGKjEVFHl5LBpTggQ7XD33VNBciSCnf3FG4K6eem3kUD6/2nieTMTqnHzQYhKSy1nY3kAkM9qa8dx0SzWIdnoBZ/M5bjTdiYxgt+HJMxzmtKiBsQdJ2PIZBzdeJjivcvb9ZOuxBX+OcqRsgC9vwz4xJsfLpEQNlFfqGkj0OrbvKBClk8q8o1mSowZlQSce2rabAUnBYfYebA== Received: from [212.82.98.53] by nm24.bullet.mail.ir2.yahoo.com with NNFMP; 26 Nov 2015 16:12:24 -0000 Received: from [212.82.98.91] by tm6.bullet.mail.ir2.yahoo.com with NNFMP; 26 Nov 2015 16:12:24 -0000 Received: from [127.0.0.1] by omp1028.mail.ir2.yahoo.com with NNFMP; 26 Nov 2015 16:12:24 -0000 X-Yahoo-Newman-Property: ymail-3 X-Yahoo-Newman-Id: 652098.89521.bm@omp1028.mail.ir2.yahoo.com X-YMail-OSG: FOK437wVM1mkPXP_y4cFLcw2Cwvl2P97TXWgEbCj54_X6lDW4O8tXpiX5kgNQ5I ItbSCrB2RDiZhnPYh9R_LLexTdwh.fV_7mPExecZ4bLJSuba0nXAVCl7_C1yj4FrGE4rI6mtpSTP EO5NE0ecznoDCIf0w4FgVFY7sll8Kl0OIFICk8f6oxCdmC23mnEeaHDVLiz_UjsvYcF7IjJRqnFA tgap3l090Ko1NTM4wbYofml.tgOnvphiOjISAeCFXZuk2b48WamLTs9NYaa6iBp9A4pXy.exGisV EUlS1SztJsGgeIGybypAxSJ73ihXVLucgy1IT0hic0qINJYE5l4FzCRoQscfzKhc1S5ZvDkac.Ur J6kRy5e4icv12AyehiWYFXl1yO.fl.E5kGPsQRWfoOQPI_Ha34kBo3OtFliT3Ed91ZR9IGAdvGQ5 GZNGpxvyqEvKOeLQKEknstI6BV.4mwLXt9loHBC3jBSkBM1LLmq8osSPWdC5SBr6XicoB11YrvX5 9.PDgnua2D5kiNg-- Received: by 212.82.98.123; Thu, 26 Nov 2015 16:12:23 +0000 Date: Thu, 26 Nov 2015 16:11:41 +0000 (UTC) From: Glyn Astill Reply-To: Glyn Astill To: Pgsql-performance Message-ID: <1077451263.18070016.1448554301343.JavaMail.yahoo@mail.yahoo.com> Subject: Index scan cost calculation MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit References: <1077451263.18070016.1448554301343.JavaMail.yahoo.ref@mail.yahoo.com> Content-Length: 4220 X-Pg-Spam-Score: -2.7 (--) 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 Hi All, Using pg 9.4.5 I'm looking at a table set up by a 3rd party application and trying to figure out why a particular index is being chosen over another for updates/deletes.