title: Custom Swift NSFetchRequest with merge, conditions, and ordering
body: <p>I'm new to Swift coming from Rails. I would like to create an NSFetchRequest with the following:</p>
  <ul>
  <li>Combining two requests (A &amp; B) where the resulting request has three records from A for every record from B.</li>
  <li>Request A is filtered by <code>type=1</code> and ordered descending by <code>createdAt</code></li>
  <li>Request B is filtered by <code>type=2</code> and random</li>
  </ul>
  <p>Is this possible?</p>