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Date: Mon, 21 May 2012 15:59:43 +0100
From: Filippo Diotalevi <filippo@ntoklo.com>
To: user@cassandra.apache.org
Message-ID: <55572E09C8F14649BE44730461642965@ntoklo.com>
Subject: Ordering counters in Cassandra
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Hi, 
I'm trying to understand what's the best design for a simple "ranking" use cases.
I have, in a row, a good number (10k - a few 100K) of counters; each one is counting the occurrence of an event. At the end of day, I want to create a ranking of the most occurred event.

What's the best approach to perform this task? 
The brute force approach of retrieving the row and ordering it doesn't work well (the call usually goes timeout, especially is Cassandra is also under load); I also don't know in advance the full set of event names (column names), so it's difficult to slice the get call.

Is there any trick to solve this problem? Maybe a way to retrieve the row ordering for counter values? 

Thanks,
-- 
Filippo Diotalevi


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                <div>
                    Hi,
                </div><div>I'm trying to understand what's the best desig=
n for a simple =22ranking=22 use cases.</div><div>I have, in a row, a goo=
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of the most occurred event.</div><div><br></div><div>What's the best appr=
oach to perform this task=3F&nbsp;</div><div>The brute force approach of =
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es timeout, especially is Cassandra is also under load); I also don't kno=
w in advance the full set of event names (column names), so it's difficul=
t to slice the get call.</div><div><br></div><div>Is there any trick to s=
olve this problem=3F Maybe a way to retrieve the row ordering for counter=
 values=3F</div>
                <div><div><br></div><div>Thanks,</div><div>--&nbsp;</div>=
<div>=46ilippo Diotalevi</div><div><br></div><div><br></div></div>
            
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