title: What will happen if queryset only return some values of model in django generic view?
body: <p>Assume:</p>
  
  <p>I have a model:</p>
  
  <pre><code>class ModelA(model):
      field a = intfield
      field b = intfiedl
  </code></pre>
  
  <p>I create a view and refine queryset:</p>
  
  <pre><code>class TestView(DetailView):
       queryset = ModelA.objects.values("a")
  </code></pre>
  
  <p>what will happen if I use this view. Will the b field of 'object' be empty or raise an error?</p>