title: Are rows sorted in Cassandra Memtable
body: <p>Are rows sorted in Memtable? According to this post:
  <a href="http://distributeddatastore.blogspot.com/2013/08/cassandra-sstable-storage-format.html" rel="nofollow noreferrer">http://distributeddatastore.blogspot.com/2013/08/cassandra-sstable-storage-format.html</a></p>
  
  <p>An index will be created when Memtable is flushed into storage (Index.db file). Having a separate index, do rows still need to be sorted in memtable ?</p>