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In-Reply-To: <4AF1F749.5050509@dehora.net>
References: <6E415F02-B17C-4559-94AA-D82903DD113C@digg.com>
	 <4AF1F749.5050509@dehora.net>
Date: Wed, 4 Nov 2009 15:54:50 -0600
Message-ID: <f4d6a21a0911041354s1fac0868md2a1f403f885c89a@mail.gmail.com>
Subject: Re: Incr/Decr Counters in Cassandra
From: Michael Greene <michael.greene@gmail.com>
To: cassandra-dev@incubator.apache.org
Cc: cassandra-user@incubator.apache.org
Content-Type: text/plain; charset=ISO-8859-1

This has come up before at http://markmail.org/thread/w3mrh4h64xpf3vuj
and http://markmail.org/message/vnmsuddlrhaziq7g
I am in favor of adding eventually-consistent atomic operations such
as this, but I'm not sure how one would implement it.  Some sort of
UUID + bloomfilter for the individual atomic operations?  I tend to
think "retrieve and increment" as requested by Jon is at odds with
eventual consistency, but maybe I'm wrong.

Michael

On Wed, Nov 4, 2009 at 3:51 PM, Bill de hOra <bill@dehora.net> wrote:
>
>
> Chris Goffinet wrote:
>>
>> Hey,
>>
>> At Digg we've been thinking about counters in Cassandra. In a lot of our
>> use cases we need this type of support from a distributed storage system.
>> Anyone else out there who has such needs as well? Zookeeper actually has
>> such support and we might use that if we can't get the support in Cassandra.
>
> I tend to need a generalization on incr/decr which is plus/minus (eg for
> quota management). Having these in Cassandra would be great.
>
> Bill
>