Return-Path: Delivered-To: apmail-cassandra-user-archive@www.apache.org Received: (qmail 92799 invoked from network); 4 May 2010 04:30:40 -0000 Received: from unknown (HELO mail.apache.org) (140.211.11.3) by 140.211.11.9 with SMTP; 4 May 2010 04:30:40 -0000 Received: (qmail 93993 invoked by uid 500); 4 May 2010 04:30:39 -0000 Delivered-To: apmail-cassandra-user-archive@cassandra.apache.org Received: (qmail 93951 invoked by uid 500); 4 May 2010 04:30:39 -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 93943 invoked by uid 99); 4 May 2010 04:30:38 -0000 Received: from athena.apache.org (HELO athena.apache.org) (140.211.11.136) by apache.org (qpsmtpd/0.29) with ESMTP; Tue, 04 May 2010 04:30:38 +0000 X-ASF-Spam-Status: No, hits=-0.2 required=10.0 tests=AWL,FREEMAIL_FROM,RCVD_IN_DNSWL_NONE,SPF_PASS,T_TO_NO_BRKTS_FREEMAIL X-Spam-Check-By: apache.org Received-SPF: pass (athena.apache.org: domain of jbellis@gmail.com designates 74.125.82.172 as permitted sender) Received: from [74.125.82.172] (HELO mail-wy0-f172.google.com) (74.125.82.172) by apache.org (qpsmtpd/0.29) with ESMTP; Tue, 04 May 2010 04:30:33 +0000 Received: by wyb32 with SMTP id 32so270436wyb.31 for ; Mon, 03 May 2010 21:30:12 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:received:mime-version:received:in-reply-to :references:from:date:message-id:subject:to:content-type; bh=grN3aWIN04o3OJPuDa+Jxav7gK+NHg/Uw7mPUfgo06Q=; b=iqOL7SpZpcXe0yOAv35+AZnSDvHpschiqbJu6koJzNGtuTl44yDxdun1607krME5ev jEMCmB81SHL2YWXN285lZOEVzY0KMovQIlL1zVqxsCs1iIy3+UgucVzXXPDPI7CmhY5I xXfQPQV83t5XRLZ281nHg33LNPeajApgyZ/hk= DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=mime-version:in-reply-to:references:from:date:message-id:subject:to :content-type; b=t97V4EKLDBdtsKNz+dIyuHoLtT1cTkOs8i1IEhMWNTkYuw38XqTMxlnnqBDewMK6wD fFe8azjiV6kU2Ru6a0TtAPJnFaboBhQnapBB/5xhczwdp5oJ6NJbN9z2TYTDKnv4xi4n B9DYLrzaFWomA1Trd0Cg3UbQ4szmN1QRee6Z8= Received: by 10.216.89.66 with SMTP id b44mr1429346wef.69.1272947411101; Mon, 03 May 2010 21:30:11 -0700 (PDT) MIME-Version: 1.0 Received: by 10.216.22.10 with HTTP; Mon, 3 May 2010 21:29:51 -0700 (PDT) In-Reply-To: References: From: Jonathan Ellis Date: Mon, 3 May 2010 23:29:51 -0500 Message-ID: Subject: Re: How do you, Bloom filter of the false positive rate or remove the problem of distributed databases? To: user@cassandra.apache.org Content-Type: text/plain; charset=ISO-8859-1 On Mon, May 3, 2010 at 8:45 PM, Kauzki Aranami wrote: > Let me rephrase my question. > > How does Cassandra deal with bloom filter's false positives on deleted records? The same way it deals with tombstones that it encounters otherwise (part of a row slice, or in a memtable). All the bloom filter does is keep you from having to check rows that don't have any data at all for a given key. Tombstones are not the same as "no data at all," we do need to propagate tombstones during replication. -- Jonathan Ellis Project Chair, Apache Cassandra co-founder of Riptano, the source for professional Cassandra support http://riptano.com