title: How to build a query for expected given result
body: <p>I have three table,</p>
  
  <p><a href="http://sqlfiddle.com/#!9/d782f/4" rel="nofollow">Fiddle Demo</a></p>
  
  <p>The problem is, its gives <code>null</code> values for another no available records in respect of all another rows</p>
  
  <p>If its possible to merge data like,</p>
  
  <pre><code>id  qtype cyu
  1   1     simple
  2   2     op
  </code></pre>