Return-Path: X-Original-To: apmail-cassandra-commits-archive@www.apache.org Delivered-To: apmail-cassandra-commits-archive@www.apache.org Received: from mail.apache.org (hermes.apache.org [140.211.11.3]) by minotaur.apache.org (Postfix) with SMTP id B0118185E4 for ; Fri, 12 Feb 2016 15:21:23 +0000 (UTC) Received: (qmail 9889 invoked by uid 500); 12 Feb 2016 15:21:18 -0000 Delivered-To: apmail-cassandra-commits-archive@cassandra.apache.org Received: (qmail 9817 invoked by uid 500); 12 Feb 2016 15:21:18 -0000 Mailing-List: contact commits-help@cassandra.apache.org; run by ezmlm Precedence: bulk List-Help: List-Unsubscribe: List-Post: List-Id: Reply-To: dev@cassandra.apache.org Delivered-To: mailing list commits@cassandra.apache.org Received: (qmail 9761 invoked by uid 99); 12 Feb 2016 15:21:18 -0000 Received: from arcas.apache.org (HELO arcas) (140.211.11.28) by apache.org (qpsmtpd/0.29) with ESMTP; Fri, 12 Feb 2016 15:21:18 +0000 Received: from arcas.apache.org (localhost [127.0.0.1]) by arcas (Postfix) with ESMTP id 55A922C1F71 for ; Fri, 12 Feb 2016 15:21:18 +0000 (UTC) Date: Fri, 12 Feb 2016 15:21:18 +0000 (UTC) From: "Aleksey Yeschenko (JIRA)" To: commits@cassandra.apache.org Message-ID: In-Reply-To: References: Subject: [jira] [Updated] (CASSANDRA-9779) Append-only optimization MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit X-JIRA-FingerPrint: 30527f35849b9dde25b450d4833f0394 [ https://issues.apache.org/jira/browse/CASSANDRA-9779?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ] Aleksey Yeschenko updated CASSANDRA-9779: ----------------------------------------- Flagged: Impediment > Append-only optimization > ------------------------ > > Key: CASSANDRA-9779 > URL: https://issues.apache.org/jira/browse/CASSANDRA-9779 > Project: Cassandra > Issue Type: New Feature > Components: CQL > Reporter: Jonathan Ellis > Fix For: 3.x > > > Many common workloads are append-only: that is, they insert new rows but do not update existing ones. However, Cassandra has no way to infer this and so it must treat all tables as if they may experience updates in the future. > If we added syntax to tell Cassandra about this ({{WITH INSERTS ONLY}} for instance) then we could do a number of optimizations: > - Compaction would only need to worry about defragmenting partitions, not rows. We could default to DTCS or similar. > - CollationController could stop scanning sstables as soon as it finds a matching row > - Most importantly, materialized views wouldn't need to worry about deleting prior values, which would eliminate the majority of the MV overhead -- This message was sent by Atlassian JIRA (v6.3.4#6332)