Return-Path: Delivered-To: apmail-cassandra-user-archive@www.apache.org Received: (qmail 81492 invoked from network); 12 Jul 2010 15:18:42 -0000 Received: from unknown (HELO mail.apache.org) (140.211.11.3) by 140.211.11.9 with SMTP; 12 Jul 2010 15:18:42 -0000 Received: (qmail 31299 invoked by uid 500); 12 Jul 2010 15:18:41 -0000 Delivered-To: apmail-cassandra-user-archive@cassandra.apache.org Received: (qmail 31261 invoked by uid 500); 12 Jul 2010 15:18:40 -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 31253 invoked by uid 99); 12 Jul 2010 15:18:40 -0000 Received: from nike.apache.org (HELO nike.apache.org) (192.87.106.230) by apache.org (qpsmtpd/0.29) with ESMTP; Mon, 12 Jul 2010 15:18:40 +0000 X-ASF-Spam-Status: No, hits=0.0 required=10.0 tests=FREEMAIL_FROM,RCVD_IN_DNSWL_NONE,SPF_PASS,T_TO_NO_BRKTS_FREEMAIL X-Spam-Check-By: apache.org Received-SPF: pass (nike.apache.org: domain of samurujackson@googlemail.com designates 209.85.212.172 as permitted sender) Received: from [209.85.212.172] (HELO mail-px0-f172.google.com) (209.85.212.172) by apache.org (qpsmtpd/0.29) with ESMTP; Mon, 12 Jul 2010 15:18:34 +0000 Received: by pxi20 with SMTP id 20so2194860pxi.31 for ; Mon, 12 Jul 2010 08:17:08 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=googlemail.com; s=gamma; h=domainkey-signature:mime-version:received:received:date:message-id :subject:from:to:content-type; bh=gs/uUQ2SyJW/FAyAyqExRywrbEMzmhdKITkzrRk6xJw=; b=j2zs0SnTMqYJdaR5r0g2wUFJu5WpckyolgiRabsuHuDOAVYoaE9KPZP7sg069mJD4P O8T9ZCPxv+iPrIaODpo/H/fRdPA3sOjttGHl5ID86toId2i4qCTx0udwMBiv8XKIjgxM MP+9vToLOFwkT6fJ4VjD7wcTctM+2/LeEHQxU= DomainKey-Signature: a=rsa-sha1; c=nofws; d=googlemail.com; s=gamma; h=mime-version:date:message-id:subject:from:to:content-type; b=gI7TMZ8acA+SGqLE1BiavfOML0nBSTlgaTXYh+n692JVaXCmZy6Kv7ZfiRwZLyxSuE u4v3yW3W+UxhbX4e3wfSRjTgSkEWt4Du5/ukuycRV4drnwmhJ230kjT2epcrmjoNfNRK 4O+0efrF2PClpj79oI7Mx444DKCNcOSZXLnfY= MIME-Version: 1.0 Received: by 10.142.185.13 with SMTP id i13mr2565985wff.247.1278947827477; Mon, 12 Jul 2010 08:17:07 -0700 (PDT) Received: by 10.142.233.2 with HTTP; Mon, 12 Jul 2010 08:17:07 -0700 (PDT) Date: Mon, 12 Jul 2010 11:17:07 -0400 Message-ID: Subject: Question regarding consistency and deletion From: Samuru Jackson To: user@cassandra.apache.org Content-Type: text/plain; charset=ISO-8859-1 X-Virus-Checked: Checked by ClamAV on apache.org Hi, I'm fairly new to Cassandra and started to set up a small cluster for playing around and evaluating it for my potential purposes. As far as I understand I can't remove whole rows - instead the columns of a deleted rows are removed and a client can decided based on the row's column count if it treats a part of a returned slice as deleted or not. Those empty rows are referenced as a Tombstone in Cassandras terminology- right? Is there any way to force the sync/garbage collection of the deletion of the such empty rows? Reading the mailinglist, this behaviour is relating to the weak consistency of Cassandra. What I don't understand is, why is it possible to remove the columns of a row, but not the whole row? Could you give me some further reading on this topic? Thanks! SJ