title: Select all rows of predefined number of distinct values
body: <p>I have a <code>User</code> table with the following rows</p>
  
  <pre><code>id: 1, favorite_id: 1
  id: 2, favorite_id: 2
  id: 3, favorite_id: 2
  id: 4, favorite_id: 3
  id: 5, favorite_id: 3
  id: 6, favorite_id: 3
  id: 7, favorite_id: 4
  id: 8, favorite_id: 4
  id: 9, favorite_id: 4
  </code></pre>
  
  <p>And looking for a query that return the first 3 distinct <code>favorite_id</code>s rows =></p>
  
  <pre><code>id: 1, favorite_id: 1
  id: 2, favorite_id: 2
  id: 3, favorite_id: 2
  id: 4, favorite_id: 3
  id: 5, favorite_id: 3
  id: 6, favorite_id: 3
  </code></pre>