Return-Path: Delivered-To: apmail-hadoop-hive-dev-archive@minotaur.apache.org Received: (qmail 7946 invoked from network); 30 Nov 2009 21:51:49 -0000 Received: from hermes.apache.org (HELO mail.apache.org) (140.211.11.3) by minotaur.apache.org with SMTP; 30 Nov 2009 21:51:49 -0000 Received: (qmail 52973 invoked by uid 500); 30 Nov 2009 21:51:48 -0000 Delivered-To: apmail-hadoop-hive-dev-archive@hadoop.apache.org Received: (qmail 52849 invoked by uid 500); 30 Nov 2009 21:51:48 -0000 Mailing-List: contact hive-dev-help@hadoop.apache.org; run by ezmlm Precedence: bulk List-Help: List-Unsubscribe: List-Post: List-Id: Reply-To: hive-dev@hadoop.apache.org Delivered-To: mailing list hive-dev@hadoop.apache.org Received: (qmail 52614 invoked by uid 99); 30 Nov 2009 21:51:44 -0000 Received: from nike.apache.org (HELO nike.apache.org) (192.87.106.230) by apache.org (qpsmtpd/0.29) with ESMTP; Mon, 30 Nov 2009 21:51:44 +0000 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; Mon, 30 Nov 2009 21:51:41 +0000 Received: from brutus (localhost [127.0.0.1]) by brutus.apache.org (Postfix) with ESMTP id DDA85234C4B0 for ; Mon, 30 Nov 2009 13:51:20 -0800 (PST) Message-ID: <714260853.1259617880906.JavaMail.jira@brutus> Date: Mon, 30 Nov 2009 21:51:20 +0000 (UTC) From: "Chaitanya Mishra (JIRA)" To: hive-dev@hadoop.apache.org Subject: [jira] Updated: (HIVE-549) Parallel Execution Mechanism In-Reply-To: <109659177.1244447167790.JavaMail.jira@brutus> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit X-JIRA-FingerPrint: 30527f35849b9dde25b450d4833f0394 X-Virus-Checked: Checked by ClamAV on apache.org [ https://issues.apache.org/jira/browse/HIVE-549?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ] Chaitanya Mishra updated HIVE-549: ---------------------------------- Attachment: (was: HIVE-549-v5.patch) > Parallel Execution Mechanism > ---------------------------- > > Key: HIVE-549 > URL: https://issues.apache.org/jira/browse/HIVE-549 > Project: Hadoop Hive > Issue Type: Wish > Components: Query Processor > Reporter: Adam Kramer > Assignee: Chaitanya Mishra > Attachments: HIVE549-v6.patch > > > In a massively parallel database system, it would be awesome to also parallelize some of the mapreduce phases that our data needs to go through. > One example that just occurred to me is UNION ALL: when you union two SELECT statements, effectively you could run those statements in parallel. There's no situation (that I can think of, but I don't have a formal proof) in which the left statement would rely on the right statement, or vice versa. So, they could be run at the same time...and perhaps they should be. Or, perhaps there should be a way to make this happen...PARALLEL UNION ALL? PUNION ALL? -- This message is automatically generated by JIRA. - You can reply to this email to add a comment to the issue online.