title: How can I have null column value for a composite key column in CQL3
body: <p>This may sound silly as there are no null values in SQL's composite primary key. But just want to confirm if we can have the same in CQL3?<br>
  So, we have a table like this to store wide rows: </p>
  
  <pre><code>CREATE TABLE keyspace12.colFamily1 
  (
    id text, 
    colname text,
    colvalue blob,
    PRIMARY KEY (id,colname, colvalue)
  ) WITH COMPACT STORAGE
  </code></pre>
  
  <p>And we have some cases where colname is null. Can I do that? If yes, then how? If NO, then what are the ways to store wide columns rows where we can have some null in first part of composite column of cassandra(As per Thrift's convention)?</p>
  
  <p>The related questions are:
  <a href="https://stackoverflow.com/questions/18699323/cql3-and-millions-of-columns-composite-key-use-case">CQL3 and millions of columns composite key use case</a> and <a href="https://stackoverflow.com/questions/12223925/cassandra-how-to-create-composite-column-name-not-key-using-cqlsh?rq=1">Cassandra -How to create composite column name (not key) using cqlsh</a></p>