Return-Path: Delivered-To: apmail-db-derby-dev-archive@www.apache.org Received: (qmail 93065 invoked from network); 26 Nov 2008 17:21:06 -0000 Received: from hermes.apache.org (HELO mail.apache.org) (140.211.11.2) by minotaur.apache.org with SMTP; 26 Nov 2008 17:21:06 -0000 Received: (qmail 57436 invoked by uid 500); 26 Nov 2008 17:21:16 -0000 Delivered-To: apmail-db-derby-dev-archive@db.apache.org Received: (qmail 57328 invoked by uid 500); 26 Nov 2008 17:21:16 -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: Delivered-To: mailing list derby-dev@db.apache.org Received: (qmail 57313 invoked by uid 99); 26 Nov 2008 17:21:16 -0000 Received: from athena.apache.org (HELO athena.apache.org) (140.211.11.136) by apache.org (qpsmtpd/0.29) with ESMTP; Wed, 26 Nov 2008 09:21:16 -0800 X-ASF-Spam-Status: No, hits=-2000.0 required=10.0 tests=ALL_TRUSTED X-Spam-Check-By: apache.org Received: from [140.211.11.140] (HELO brutus.apache.org) (140.211.11.140) by apache.org (qpsmtpd/0.29) with ESMTP; Wed, 26 Nov 2008 17:19:58 +0000 Received: from brutus (localhost [127.0.0.1]) by brutus.apache.org (Postfix) with ESMTP id 632FB234C2AA for ; Wed, 26 Nov 2008 09:20:44 -0800 (PST) Message-ID: <1203821569.1227720044405.JavaMail.jira@brutus> Date: Wed, 26 Nov 2008 09:20:44 -0800 (PST) From: "Dag H. Wanvik (JIRA)" To: derby-dev@db.apache.org Subject: [jira] Commented: (DERBY-481) implement SQL generated columns MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit X-Virus-Checked: Checked by ClamAV on apache.org [ https://issues.apache.org/jira/browse/DERBY-481?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=12651068#action_12651068 ] Dag H. Wanvik commented on DERBY-481: ------------------------------------- Looked at derby-481-13-aa-alterDatatype.diff, looks good! Thanks. > implement SQL generated columns > ------------------------------- > > Key: DERBY-481 > URL: https://issues.apache.org/jira/browse/DERBY-481 > Project: Derby > Issue Type: New Feature > Components: SQL > Affects Versions: 10.0.2.1 > Reporter: Rick Hillegas > Assignee: Rick Hillegas > Attachments: derby-481-00-aa-prototype.diff, derby-481-01-aa-catalog.diff, derby-481-02-aa-utilities.diff, derby-481-03-aa-grammar.diff, derby-481-04-aa-insert.diff, derby-481-05-aa-update.diff, derby-481-06-aa-genreferences.diff, derby-481-07-aa-noSQLinRoutines.diff, derby-481-07-ab-noSQLinRoutines.diff, derby-481-08-aa-castToDeclaredType.diff, derby-481-09-aa-dummyDefaults.diff, derby-481-10-aa-foreignKeyActions.diff, derby-481-11-aa-notNull.diff, derby-481-12-aa-padding.diff, derby-481-13-aa-alterDatatype.diff, derby-481-14-ab-dropColumn.diff, derby-481-15-aa-renameAndAddDefault.diff, derby-481-16-aa-dropFunction.diff, derby-481-17-aa-currentSchema.diff, derby-481-18-aa-updatableResultSets.diff, derby-481-19-aa-cleanup.diff, GeneratedColumns.html, GeneratedColumns.html, GeneratedColumns.html > > > Satheesh has pointed out that generated columns, a SQL 2003 feature, would satisfy the performance requirements of Expression Indexes (bug 455). Generated columns may not be as elegant as Expression Indexes, but they are easier to implement. We would allow the following new kind of column definition in CREATE TABLE and ALTER TABLE statements: > columnName GENERATED ALWAYS AS ( expression ) > If expression were an indexableExpression (as defined in bug 455), then we could create indexes on it. There is no work for the optimizer to do here. The Language merely has to compute the generated column at INSERT/UPDATE time. -- This message is automatically generated by JIRA. - You can reply to this email to add a comment to the issue online.