title: django delete problem - deleting more than one object with a OneToOneField relationship - got MultipleObjectsReturned error
body: <p>I have a problem with deleting my objects. I wrote a delete method which get a list of IDs of objects to be deleted. This works fine for objects and for objects with foreign keys, but it fails if i have a OneToOneField relationship to the object which i want to delete.</p>
  
  <p>This is my delete method:</p>
  
  <pre><code>@login_required
  def delete_objects(request, model, selected_ids):
      '''
      capsulate a bulk delete method
      delete all objects found for the given model
      fails silently since model.delete() always fails silently
      '''
      object_list = model.objects.filter(pk__in=selected_ids)
      count = object_list.count()
      if count == 1:
          name = model._meta.verbose_name.title()
      else:
          name = model._meta.verbose_name_plural.title()
      object_list.delete()
      request.user.message_set.create(message='Successfully deleted %s %s' % (count,name))
      return
  </code></pre>
  
  <p>Till now I just tested it with Contact objects. Now I added a PhoneNumber model to my models. The PhoneNumber model has a OneToOneField relationship to the Contact model. If no PhoneNumber object or one PhoneNumber object is assigned to the Contact object i can delete it. But if I relate more than one PhoneNumber object to a Contact object i get an error.</p>
  
  <p>This is the error message that i get:</p>
  
  <pre><code>MultipleObjectsReturned at /crm/contacts/
  get() returned more than one PhoneNumber -- it returned 3! Lookup parameters were {'contact__pk': 4L}
  Request Method: POST
  Request URL:    http://127.0.0.1:8000/crm/contacts/
  Exception Type: MultipleObjectsReturned
  Exception Value:    
  get() returned more than one PhoneNumber -- it returned 3! Lookup parameters were {'contact__pk': 4L}
  </code></pre>
  
  <p>I read in the django docs </p>
  
  <p><a href="http://docs.djangoproject.com/en/dev/topics/db/queries/#deleting-objects" rel="nofollow noreferrer">deleting objects</a></p>
  
  <p>that "any objects which had foreign keys pointing at the object to be deleted will be deleted along with it." This is the goal I want to accomplish.. but now i get an error. All I want is the objects to be deleted :D</p>
  
  <p>Actually is this maybe a design problem? Is it wrong when I relate more than one PhoneNumber object to a Contact object with a OneToOneField relationship? I have chosen OneToOneField since the phone number is unique and should be related to only one contact.</p>