X-Original-To: pgsql-hackers-postgresql.org@localhost.postgresql.org Received: from localhost (unknown [200.46.204.144]) by svr1.postgresql.org (Postfix) with ESMTP id ECDDBD1B79C for ; Thu, 1 Jul 2004 18:09:03 -0300 (ADT) Received: from svr1.postgresql.org ([200.46.204.71]) by localhost (av.hub.org [200.46.204.144]) (amavisd-new, port 10024) with ESMTP id 83811-05 for ; Thu, 1 Jul 2004 21:08:53 +0000 (GMT) Received: from mproxy.gmail.com (rproxy.gmail.com [64.233.170.206]) by svr1.postgresql.org (Postfix) with SMTP id 387FED1B783 for ; Thu, 1 Jul 2004 18:08:49 -0300 (ADT) Received: by mproxy.gmail.com with SMTP id m69so3266rne for ; Thu, 01 Jul 2004 14:08:51 -0700 (PDT) Received: by 10.38.171.54 with SMTP id t54mr20116rne; Thu, 01 Jul 2004 14:08:51 -0700 (PDT) Message-ID: Date: Thu, 1 Jul 2004 23:08:51 +0200 From: Jochem van Dieten To: Bruno Wolff III Subject: Re: Adding column comment to information_schema.columns Cc: PostgreSQL Hackers Mailing List In-Reply-To: <20040701172310.GA2908@wolff.to> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit References: <40E37E3F.2050400@telstra.net> <22066.1088656403@sss.pgh.pa.us> <40E3949F.6020201@telstra.net> <40E3BB25.4020804@pse-consulting.de> <20040701172310.GA2908@wolff.to> X-Virus-Scanned: by amavisd-new at hub.org X-Spam-Status: No, hits=0.0 tagged_above=0.0 required=5.0 tests= X-Spam-Level: X-Archive-Number: 200407/53 X-Sequence-Number: 55614 On Thu, 1 Jul 2004 12:23:10 -0500, Bruno Wolff III wrote: > > Is there any provision in the information schema part of the standard for > vendor specific extensions? Yes, there is: "An SQL-implementation may define objects that are associated with INFORMATION_SCHEMA that are not defined in this Clause. An SQL-implementation or any future version of ISO/IEC 9075 may also add columns to tables that are defined in this Clause." ISO/IEC 9075-11:2003 4.2 Introduction to the Information Schema If we combine this with the promise that no object defined by the standard will ever end in an underscore, I can think of no reason not to add PostgreSQL specific columns as long as they end in an underscore. The underscore will not only prevent conflicts with future versions of the standard, it will also serve as a warning that that column is a PostgreSQL extension. Jochem PS I think I spotted an inconsistency in the standard. It says "to tables that are defined in this Clause", while the Clause only defines views, not tables.