Return-Path: Delivered-To: apmail-cassandra-user-archive@www.apache.org Received: (qmail 9959 invoked from network); 13 May 2010 19:48:56 -0000 Received: from unknown (HELO mail.apache.org) (140.211.11.3) by 140.211.11.9 with SMTP; 13 May 2010 19:48:56 -0000 Received: (qmail 25721 invoked by uid 500); 13 May 2010 19:48:55 -0000 Delivered-To: apmail-cassandra-user-archive@cassandra.apache.org Received: (qmail 25702 invoked by uid 500); 13 May 2010 19:48:55 -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 25694 invoked by uid 99); 13 May 2010 19:48:55 -0000 Received: from athena.apache.org (HELO athena.apache.org) (140.211.11.136) by apache.org (qpsmtpd/0.29) with ESMTP; Thu, 13 May 2010 19:48:55 +0000 X-ASF-Spam-Status: No, hits=2.2 required=10.0 tests=FREEMAIL_FROM,HTML_MESSAGE,SPF_PASS,T_TO_NO_BRKTS_FREEMAIL X-Spam-Check-By: apache.org Received-SPF: pass (athena.apache.org: domain of stevelihn@gmail.com designates 209.85.161.44 as permitted sender) Received: from [209.85.161.44] (HELO mail-fx0-f44.google.com) (209.85.161.44) by apache.org (qpsmtpd/0.29) with ESMTP; Thu, 13 May 2010 19:48:49 +0000 Received: by fxm16 with SMTP id 16so310089fxm.31 for ; Thu, 13 May 2010 12:48:27 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=domainkey-signature:mime-version:received:received:in-reply-to :references:date:message-id:subject:from:to:content-type; bh=df8D1KGtU/yX/KNH2FRS6pR+RrMNU+iRVvwTBvihwUk=; b=J05lOr8jgezJ0FF9TQVV+tTuBGDpo0t7JuYg28n1hIjUHdl6VjiTt8ZkNF0ddChArn Iq24tiodCFQCJyJhmi/VGIH1Efgg2qFlAOEinxFXl9h/AA+PjT6Vh3PulJb1W7xdEh7O I7Nqobf2nyHtGk/ZjOU/iPn80J/J7TS/nyBjs= DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :content-type; b=IJTDfMO4Wg5f2rpl5PqUzJFZbkp3Vl/KyxwcvjYEdwsTt6hQKT13MfBLW+Ol6eENJ3 Km28ozSccdT8hTilGJnU9e6bMU1gl8ZRWeAx5SLDc1ExaLqKwftud/RPwLvqjKL5Fuj8 c27GjeW2baX7dgaY8Z26W0eWrPm0Ryiy2OuCU= MIME-Version: 1.0 Received: by 10.103.209.9 with SMTP id l9mr298518muq.64.1273780107474; Thu, 13 May 2010 12:48:27 -0700 (PDT) Received: by 10.103.233.6 with HTTP; Thu, 13 May 2010 12:48:27 -0700 (PDT) In-Reply-To: References: Date: Thu, 13 May 2010 15:48:27 -0400 Message-ID: Subject: Re: how does cassandra compare with mongodb? From: Steve Lihn To: user@cassandra.apache.org Content-Type: multipart/alternative; boundary=002215b02122d3f90604867f0ad3 --002215b02122d3f90604867f0ad3 Content-Type: text/plain; charset=UTF-8 What is changing? A more flexible schema or no need to restart (some kind of hot-reboot)? Mongo guys claims that Mongo's advantage is a schema-less design. Basically you can have any data structure you want and you can change them anyway you want. This is done in the name of "flexibility", but I am not sure this is a good practice. People argued for years that perl is bad because it is typeless and java is strong typed and is better. Now the java community is developing a database like Mongo that is schema-less. How does this complements the strong-type argument? The less requirement is put on database schema design, the more burden is put on the application to maintain data integrity. Why is this a good trend? Can someone kindly explain? Steve On Thu, May 13, 2010 at 1:22 PM, Vijay wrote: > "Cassandra requires the schema to be defined before the database starts, > MongoDB can have any schema at run-time just like a normal database." > > This is changing in 0.7 > > Regards, > > > > --002215b02122d3f90604867f0ad3 Content-Type: text/html; charset=UTF-8 Content-Transfer-Encoding: quoted-printable What is changing? A more flexible schema or no need to restart (some kind o= f hot-reboot)?

Mongo guys claims that Mongo's advantage is a sch= ema-less design. Basically you can have any data structure you want and you= can change them anyway you want. This is done in the name of "flexibi= lity", but I am not sure this is a good practice. People argued for ye= ars that perl is bad because it is typeless and java is strong typed and is= better. Now the java community is developing a database like Mongo that is= schema-less. How does this complements the strong-type argument?

The less requirement is put on database schema design, the more burden = is put on the application to maintain data integrity. Why is this a good tr= end? Can someone kindly explain?

Steve



On Thu, May 13, 2010 at 1:22 PM, Vijay <vijay2win@gmail.com> wrote:
"Cassandra requires the schema = to be defined before the database starts, MongoDB can have any schema at ru= n-time just like a normal database."

This is changing in 0.7

Regards,
</VJ>


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