-----Original Message----- From: pgsql-admin-owner@xxxxxxxxxxxxxx [mailto:pgsql-admin-owner@xxxxxxxxxxxxxx] On Behalf Of Thomas Kellerer Sent: 25 March 2015 01:05 PM To: pgsql-admin@xxxxxxxxxxxxxx Subject: Re: Postgres 9 : - How to interpret the EXPLAIN query results Khangelani Gama schrieb am 25.03.2015 um 11:28: > Thanks to all, but if this total cost is the total time it will take to > retrieve the output then is it in minutes or milliseconds? > If it’s in milliseconds does it mean that it take about 213 hrs for a > total of 768375132.77 No. The cost is not the total time. Quote from the manual measured in cost units that are arbitrary, but conventionally mean disk page fetches In general you can _assume_ that a query with a higher cost is likely to run longer than an equivalent query with lower costs. If you want the runtime of each step you need to use "explain (analyze)" - again this is documented in the manual. Thomas Many Thanks Thomas -- Sent via pgsql-admin mailing list (pgsql-admin@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-admin CONFIDENTIALITY NOTICE The contents of and attachments to this e-mail are intended for the addressee only, and may contain the confidential information of Argility (Proprietary) Limited and/or its subsidiaries. Any review, use or dissemination thereof by anyone other than the intended addressee is prohibited.If you are not the intended addressee please notify the writer immediately and destroy the e-mail. Argility (Proprietary) Limited and its subsidiaries distance themselves from and accept no liability for unauthorised use of their e-mail facilities or e-mails sent other than strictly for business purposes. -- Sent via pgsql-admin mailing list (pgsql-admin@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-admin
