Received: from maia.hub.org (maia-2.hub.org [200.46.204.251]) by mail.postgresql.org (Postfix) with ESMTP id 3A50EB5DC03 for ; Wed, 19 Oct 2011 07:47:28 -0300 (ADT) Received: from mail.postgresql.org ([200.46.204.86]) by maia.hub.org (mx1.hub.org [200.46.204.251]) (amavisd-maia, port 10024) with ESMTP id 59459-07 for ; Wed, 19 Oct 2011 10:47:22 +0000 (UTC) X-Greylist: from auto-whitelisted by SQLgrey-1.8.0-rc2 Received: from rs133.luxsci.com (rs133.luxsci.com [72.32.115.26]) by mail.postgresql.org (Postfix) with ESMTP id 20DBDB5DC5E for ; Wed, 19 Oct 2011 07:47:21 -0300 (ADT) Received: from GNANAM (NSG-Static-233.156.72.182.airtel.in [182.72.156.233] (may be forged)) (authenticated bits=0) by rs133.luxsci.com (8.13.8/8.13.8) with ESMTP id p9JAkvBX026533; Wed, 19 Oct 2011 05:47:20 -0500 Reply-To: From: "Gnanakumar" To: Subject: Inner Join - Explicit vs Implicit Join Performance Date: Wed, 19 Oct 2011 16:09:44 +0530 Organization: Zoniac Software Private Limited Message-ID: <002301cc8e4b$6d147390$473d5ab0$@com> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit X-Mailer: Microsoft Office Outlook 12.0 Thread-Index: AcyOS2jVI3ta0bvPTwCUrUmzEVNmIw== Content-Language: en-us X-Virus-Scanned: Maia Mailguard 1.0.1 X-Spam-Status: No, hits=-1.9 tagged_above=-10 required=5 tests=BAYES_00=-1.9 X-Spam-Level: X-Archive-Number: 201110/158 X-Sequence-Number: 45380 Hi, In PostgreSQL, is there any performance difference between queries written using "explicit join notation" vs "implicit join notation" in complex queries? EXAMPLE: Simple "explicit join notation" SELECT * FROM employee INNER JOIN department ON employee.DepartmentID = department.DepartmentID; EXAMPLE: Simple "implicit join notation" SELECT * FROM employee, department WHERE employee.DepartmentID = department.DepartmentID; Regards, Gnanam