[1.1.X] Fixed #11931: Removed mention of nonexistent get_sql() method…

… for arguments to limit_choices_to. Since the correct reference involves undocumented ORM internals, this simply removes the reference entirely in favor of publicly-documented use of Q objects. Backport of [11591] from trunk.

git-svn-id: http://code.djangoproject.com/svn/django/branches/releases/1.1.X@11592 bcc190cf-cafb-0310-a4f2-bffc1f526a37

docs/ref/models/fields.txt

@@ -844,7 +844,7 @@ define the details of how the relation works.
     current date/time to be chosen.
 
     Instead of a dictionary this can also be a :class:`~django.db.models.Q`
-    object (an object with a :meth:`get_sql` method) for more complex queries.
+    object for more :ref:`complex queries <complex-lookups-with-q>`.
 
     ``limit_choices_to`` has no effect on the inline FormSets that are created
     to display related objects in the admin.

docs/topics/db/queries.txt

@@ -622,6 +622,8 @@ To avoid this problem, simply save the ``QuerySet`` and reuse it::
     >>> print [p.headline for p in queryset] # Evaluate the query set.
     >>> print [p.pub_date for p in queryset] # Re-use the cache from the evaluation.
 
+.. _complex-lookups-with-q:
+
 Complex lookups with Q objects
 ==============================