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Date: Wed, 29 Sep 2010 00:14:25 -0500
Message-ID: <AANLkTimL7EbRNREXX-tPO0DbgV2KO-QebYB8PrJDTgsX@mail.gmail.com>
Subject: Re: [DISCUSSION] High-volume counters in Cassandra
From: Jonathan Ellis <jbellis@gmail.com>
To: dev <dev@cassandra.apache.org>
Content-Type: text/plain; charset=ISO-8859-1

On Tue, Sep 28, 2010 at 4:00 PM, Sylvain Lebresne <sylvain@yakaz.com> wrote:
> I agree that it is worth adding a support for counter as supercolumns
> in 1546 and that's fairly trivial, so I will add that as soon as possible
> (but please understand that I'm working on this for a good part during
> my free time).
>
> As for supercolumns of counters, there is what Jonathan proposes, but
> I'll add that encoding a supercolumns CF to a standard column CF is
> almost always a fairly trivial encoding. Worst case scenario it requires
> you to roll up your own comparator and it's slightly less convenient
> for client code.

Supporting supercolumns to allow multiple counters per row, but
requiring encoding with a custom comparator for deeper nesting, seems
like a reasonable compromise to me.

Ryan, while this obviously isn't ideal from your perspective of
already having code written against supercolumns-of-counters, is it
something you could live with?

In exchange we get 1072 + 1210 + 1397 + 1375 + ConsistencyLevel
support for substantially less code (= less complexity and special
cases) than 1072 alone.

-- 
Jonathan Ellis
Project Chair, Apache Cassandra
co-founder of Riptano, the source for professional Cassandra support
http://riptano.com