Return-Path: Delivered-To: apmail-db-derby-dev-archive@www.apache.org Received: (qmail 29233 invoked from network); 4 Mar 2005 09:39:51 -0000 Received: from hermes.apache.org (HELO mail.apache.org) (209.237.227.199) by minotaur-2.apache.org with SMTP; 4 Mar 2005 09:39:51 -0000 Received: (qmail 39380 invoked by uid 500); 4 Mar 2005 09:39:50 -0000 Delivered-To: apmail-db-derby-dev-archive@db.apache.org Received: (qmail 39349 invoked by uid 500); 4 Mar 2005 09:39:50 -0000 Mailing-List: contact derby-dev-help@db.apache.org; run by ezmlm Precedence: bulk list-help: list-unsubscribe: List-Post: List-Id: Reply-To: "Derby Development" Delivered-To: mailing list derby-dev@db.apache.org Received: (qmail 39335 invoked by uid 99); 4 Mar 2005 09:39:50 -0000 X-ASF-Spam-Status: No, hits=0.0 required=10.0 tests= X-Spam-Check-By: apache.org Received-SPF: pass (hermes.apache.org: local policy) Received: from brmea-mail-3.Sun.COM (HELO brmea-mail-3.sun.com) (192.18.98.34) by apache.org (qpsmtpd/0.28) with ESMTP; Fri, 04 Mar 2005 01:39:48 -0800 Received: from phys-lego-1.Norway.Sun.COM ([129.159.112.5]) by brmea-mail-3.sun.com (8.12.10/8.12.9) with ESMTP id j249dkhl011484 for ; Fri, 4 Mar 2005 02:39:46 -0700 (MST) Received: from clustra.norway.sun.com (clustra [129.159.113.10]) by phys-lego-1.Norway.Sun.COM (8.12.10+Sun/8.12.10/ENSMAIL,v2.3beta1412) with SMTP id j249dj4d021082 for ; Fri, 4 Mar 2005 10:39:45 +0100 (MET) Received: (qmail 21840 invoked from network); 4 Mar 2005 09:39:45 -0000 Received: from atum01.norway.sun.com (129.159.112.201) by clustra.norway.sun.com with QMQP; 4 Mar 2005 09:39:45 -0000 Date: Fri, 4 Mar 2005 10:39:45 +0100 From: "Bernt M. Johnsen" To: Derby Development Subject: UNIQUE constraint on posisble null columns (Was: DB2 mode vs. Cloudscape mode) Message-ID: <20050304093945.GA26412@atum01.norway.sun.com> References: <20050303203321.GA16736@atum01.norway.sun.com> <42277A5B.9090406@Sourcery.Org> <42277C96.2040805@apache.org> <4227AE2F.20909@Sourcery.Org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <4227AE2F.20909@Sourcery.Org> Organization: Sun Microsystems User-Agent: Mutt/1.5.6i X-Virus-Checked: Checked X-Spam-Rating: minotaur-2.apache.org 1.6.2 0/1000/N >>>>>>>>>>>> Satheesh Bandaram wrote (2005-03-03 16:39:11): > Yes, Cloudscape used to allow creating UNIQUE indexes on null columns, > but in a non-standard way. Old cloudscape used to allow only one NULL > value in the UNIQUE index, where as, I think the standard required > multiple NULL values. I think that behaviour was Oracle compliant. > I think making Derby handle multiple NULLs in UNIQUE index needs changes > to store/indexing. Anyway, UNIQUE constraint on possible null columns (SQl-99 Feature T591) is a non-Core SQL-99 feature. -- Bernt Marius Johnsen, HA Data Management, Sun Microsystems, Norway ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ NOTICE: This signature is neither personal, religious, literary, ethnic, racial, offensive nor humorous.