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Date: Tue, 15 Feb 2011 19:11:57 -0600
Message-ID: <AANLkTikg0NXgzY-2y4K=kqf8UeaHzzcAdhsUbCJJCjDH@mail.gmail.com>
Subject: Re: latest rows
From: Tyler Hobbs <tyler@datastax.com>
To: user@cassandra.apache.org
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> What is the best way to retrieve the latest rows from a CF with OPP.
>

Use inverted timestamps (for example, 2^64 - timestamp) with zeros for
padding as the row keys.

This way you can do a normal forward range scan and get the N latest rows.

-- 
Tyler Hobbs
Software Engineer, DataStax <http://datastax.com/>
Maintainer of the pycassa <http://github.com/pycassa/pycassa> Cassandra
Python client library

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<div class="gmail_quote"><br><blockquote class="gmail_quote" style="margin: 0pt 0pt 0pt 0.8ex; border-left: 1px solid rgb(204, 204, 204); padding-left: 1ex;">
What is the best way to retrieve the latest rows from a CF with OPP.<font color="#888888"><br>
</font></blockquote></div><br>Use inverted timestamps (for example, 2^64 - timestamp) with zeros for padding as the row keys.<br clear="all"><br>This way you can do a normal forward range scan and get the N latest rows.<br>
<br>-- <br><font color="#888888">Tyler Hobbs<span></span><br>
Software Engineer, <a href="http://datastax.com/" target="_blank">DataStax</a><br>Maintainer of the <a href="http://github.com/pycassa/pycassa" target="_blank">pycassa</a> Cassandra Python client library<br></font><br>

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