From user-return-27948-apmail-cassandra-user-archive=cassandra.apache.org@cassandra.apache.org Thu Aug 2 10:47:38 2012 Return-Path: X-Original-To: apmail-cassandra-user-archive@www.apache.org Delivered-To: apmail-cassandra-user-archive@www.apache.org Received: from mail.apache.org (hermes.apache.org [140.211.11.3]) by minotaur.apache.org (Postfix) with SMTP id E9A6DDFCA for ; Thu, 2 Aug 2012 10:47:37 +0000 (UTC) Received: (qmail 63130 invoked by uid 500); 2 Aug 2012 10:47:35 -0000 Delivered-To: apmail-cassandra-user-archive@cassandra.apache.org Received: (qmail 62916 invoked by uid 500); 2 Aug 2012 10:47:35 -0000 Mailing-List: contact user-help@cassandra.apache.org; run by ezmlm Precedence: bulk List-Help: List-Unsubscribe: List-Post: List-Id: Reply-To: user@cassandra.apache.org Delivered-To: mailing list user@cassandra.apache.org Received: (qmail 62890 invoked by uid 99); 2 Aug 2012 10:47:34 -0000 Received: from athena.apache.org (HELO athena.apache.org) (140.211.11.136) by apache.org (qpsmtpd/0.29) with ESMTP; Thu, 02 Aug 2012 10:47:34 +0000 X-ASF-Spam-Status: No, hits=-0.0 required=5.0 tests=SPF_PASS X-Spam-Check-By: apache.org Received-SPF: pass (athena.apache.org: domain of Owen.Davies@logmein.com designates 173.48.77.106 as permitted sender) Received: from [173.48.77.106] (HELO usmx2.logmein.com) (173.48.77.106) by apache.org (qpsmtpd/0.29) with ESMTP; Thu, 02 Aug 2012 10:47:29 +0000 Received: from bp-mailhub02.3amlabs.net (192.168.0.184) by us-mailhub01.3amlabs.net (192.168.20.239) with Microsoft SMTP Server (TLS) id 8.2.255.0; Thu, 2 Aug 2012 06:47:08 -0400 DKIM-Signature: v=1; a=rsa-sha1; c=relaxed/relaxed; s=s1024;d=logmein.com; h=from:to:date:subject:message-id:content-type:mime-version; bh=q64U9b59uH0sYdaabssRxCPmW1Q=; b=qfCETqxzPbS5cgn7eYy2w3KQ+UKgE2BSRVejlSAs6K9oAMatLh7GeIy140fO2fTTDjlAhOdM Do6z2F1sMGMiPn8aaUwm+KD66h4cpY1T1QjKbMBpiFtLMu4TDsbPx02ksn+kPsFECyuIl8D3 v0uXGKlW9QVyraU/cw7tDto1v+N5Vsk1hQ7/ta0T/XdZDgHa86et50cWV2xJ0y0hSWYjXrNm wZK6TpIOMmCHrGQIOr8m9WSdWt6spW2b5OJlWpMe4k1G/7mnKa3HD9s+m+BtNGXB5ime2xti 3az/NVvcALrY0QZBXVmuk9+3KgcNq0dIocps0yo/DAFUZLqFHz654g== DomainKey-Signature: a=rsa-sha1; q=dns; c=nofws; s=s1024;d=logmein.com; h=from:to:date:subject:message-id:content-type:mime-version; b=zA1qNSpTJP9hEBRuYyh/f7mjzbzXTGxhqFHuWxsPJ3FPqlSqosbqQ1+toh9e3ooB+VgMX9DC FTlddAWt4i36X/X1Hf37Lz6CpuoqH8qK1KsgY48scoq4BRMmTluDAdOoWRdhNQlKv+XDhtXQ N+2yHNKB1VhUlU95elzUxxIjJMNyLvRBP6b/RfFBh0obhKjRFpQGpZqEk3VjSMn7SjtLcPJG XWZeJBGvSLvpGbxICvu9QTTY7unjl8FpBelVOVxKKUknyYONp1VA/+MEc9XmhmhPpxa2tCtS s8PKFQrlXnI5XgWY3hXhqMmchm3ldmJIjUAFJ1j1jdiJb+pjiPIVyw== Received: from MAIL06.3amlabs.net ([192.168.0.183]) by bp-mailhub02.3amlabs.net ([192.168.0.184]) with mapi; Thu, 2 Aug 2012 12:47:04 +0200 From: Owen Davies To: "user@cassandra.apache.org" Date: Thu, 2 Aug 2012 12:47:04 +0200 Subject: Is large number of columns per row a problem? Thread-Topic: Is large number of columns per row a problem? Thread-Index: AQHNcJwnXGQ7ZNe1pE6lu4ep9XVZAw== Message-ID: Accept-Language: en-US Content-Language: en-GB X-MS-TNEF-Correlator: acceptlanguage: en-US Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 X-EMS-Proccessed: V2lIcTVFKD1dHRXOvVFUSg== X-EMS-STAMP: agTsTtpOpZC9WdTngaBXgQ== X-Virus-Checked: Checked by ClamAV on apache.org We want to store a large number of columns in a single row (up to about 100= ,000,000), where each value is roughly 10 bytes. We also need to be able to get slices of columns from any point in the row. We haven't found a problem with smaller amounts of data so far, but can any= one think of any reason if this is a bad idea, or would cause large perform= ance problems? If breaking up the row is something we should do, what is the maximum numbe= r of columns we should have? We are not too worried if there is only a small performance decrease, addin= g more nodes to the cluster would be an option to help make code simpler. Thanks, Owen Davies=