title: How to do Minus HQL
body: <p>I have a table A{id, foo, ...} and a table B{id, boo, idA}
  I want All objects in A that the ids doesn't appear in B</p>
  
  <p>in Oracle SQL would looks like:</p>
  
  <pre><code>SELECT id FROM A MINUS( SELECT idA FROM B);
  </code></pre>