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 4D84A9C25 for ; Wed, 5 Oct 2011 18:10:30 +0000 (UTC) Received: (qmail 9197 invoked by uid 500); 5 Oct 2011 18:10:28 -0000 Delivered-To: apmail-cassandra-user-archive@cassandra.apache.org Received: (qmail 9114 invoked by uid 500); 5 Oct 2011 18:10:28 -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 9100 invoked by uid 99); 5 Oct 2011 18:10:28 -0000 Received: from athena.apache.org (HELO athena.apache.org) (140.211.11.136) by apache.org (qpsmtpd/0.29) with ESMTP; Wed, 05 Oct 2011 18:10:28 +0000 X-ASF-Spam-Status: No, hits=-0.0 required=5.0 tests=RCVD_IN_DNSWL_NONE,SPF_PASS X-Spam-Check-By: apache.org Received-SPF: pass (athena.apache.org: local policy) Received: from [64.78.56.90] (HELO hub025-ca-6.exch025.serverdata.net) (64.78.56.90) by apache.org (qpsmtpd/0.29) with ESMTP; Wed, 05 Oct 2011 18:10:16 +0000 Received: from [10.100.0.17] (74.202.214.86) by west.exch025.serverdata.net (10.254.12.231) with Microsoft SMTP Server (TLS) id 14.1.289.1; Wed, 5 Oct 2011 11:09:55 -0700 Message-ID: <4E8C9D60.7000109@likewise.com> Date: Wed, 5 Oct 2011 11:09:36 -0700 From: Don Smith User-Agent: Mozilla/5.0 (X11; U; Linux x86_64; en-US; rv:1.9.2.21) Gecko/20110831 Thunderbird/3.1.13 MIME-Version: 1.0 To: Subject: Question about sharding of rows and atomicity References: In-Reply-To: Content-Type: text/plain; charset="ISO-8859-1"; format=flowed Content-Transfer-Encoding: 7bit Does Cassandra shard the columns of a single row across multiple nodes so that to read the columns of the row it may need access to multiple nodes? I'd say "no." Will a read from a given node ever return partial results or is the write to a node of a row atomic? Thanks, Don