title: Spring JPA PageRequest ordering by a join column
body: <p>I'm using the Spring PageRequest to sort (order) a custom query by a column in my database.</p>
  
  <p>If I'm doing a custom query such as :</p>
  
  <pre><code> @Query( value = "select h from hunterhouse h join h.queens q where q.name = 'Computer Science'") 
  </code></pre>
  
  <p>Is it not possible to sort by a column in q, the table I am joining to?</p>
  
  <pre><code>PageRequest request = new PageRequest(page, size, Sort.Direction.DESC, "q.region");
  </code></pre>
  
  <p>debug comes out as "order by h.q.region" which is incorrect, is it not possible to order by a join column?</p>