title: CQL: how to check if keyspace exists?
body: <p>I need to check if certain keyspace exists in Cassandra database. I need to write smth like this:</p>
  
  <pre><code>if (keyspace KEYSPACE_NAME not exists) create keyspace KEYSPACE_NAME;
  </code></pre>
  
  <p>There's a command describe keyspace, but can I somehow retrieve information from it in cql script?</p>