Some people will shoot themselves in the foot with this. That's bad luck.
The reason we need it is because some data semantics cannot be expressed in
Django's ORM and that shouldn't prevent ordering on that data. For example,
filtering suburbs by a geographic region and then ordering on the suburb names.
The names might not be unique outside that region, but unique inside it. Django
cannot know that (you can't tell the model about it), so we trust the caller.
git-svn-id: http://code.djangoproject.com/svn/django/branches/queryset-refactor@7285 bcc190cf-cafb-0310-a4f2-bffc1f526a37