title: Cassandra Update or Insert when KEY already exists as Batch
body: <p>I imagine with Cassandra 2.0 + using CQL this will look something like</p>
  
  <pre><code>BATCH BEGIN;
  UPDATE keyspace.Table SET column = "value" IF EXISTS
  INSERT keyspace.Table (...) VALUES (...) IF NOT EXISTS
  BATCH END;
  </code></pre>
  
  <p>basically two statements for each item to be inserted/updated; This basically should mimic the MERGE behaviour of T-SQL</p>
  
  <p>Is this a right assumption for the task I'd like to perform?</p>