title: Using select_related to get values two models away
body: <p>Lets say I have the following:</p>
  
  <pre><code>class Model1(Model):
  
      field1 = ForeignKey(Model2)
      query_field = IntegerField()
  
  class Model2(Model):
      field2 = ForeignKey(Model3)
  
  class Model3(Model)
      field3 = SomeDesiredValue
  </code></pre>
  
  <p>Now I want to do a query on the <code>Model1</code> table and pull out <code>field3</code> from <code>Model3</code>.  My question is on performance of <code>select_related</code>.</p>
  
  <p>If I do</p>
  
  <pre><code>query = Model1.objects.filter(query_field=filter_paramter).select_related('field1')
  </code></pre>
  
  <p>I'm assuming the following will still hit the database?</p>
  
  <pre><code>query[0].field1.field2.field3
  </code></pre>
  
  <p>Can I do the following to make it faster?</p>
  
  <pre><code>query = Model1.objects.filter(query_field=filter_paramter).select_related('field1__field2')
  </code></pre>