Ticket #12567: 12567.2.diff

django/db/models/sql/query.py

@@ -1015 +1015 @@
 
         # Process the join list to see if we can remove any inner joins from
         # the far end (fewer tables in a query is better).
-        col, alias, join_list = self.trim_joins(target, join_list, last, trim)
+        if (lookup_type == 'isnull' and value is False and not negate and
+                len(join_list) > 1):
+            col = target.column
+            alias = join_list[-1]
+        else:
+            col, alias, join_list = self.trim_joins(target, join_list, last, trim)
 
         if connector == OR:
             # Some joins may need to be promoted when adding a new filter to a

tests/regressiontests/model_inheritance_regress/models.py

@@ -6 +6 @@
 
 from django.db import models
 
-# Python 2.3 doesn't have sorted()
-try:
-    sorted
-except NameError:
-    from django.utils.itercompat import sorted
 
 class Place(models.Model):
     name = models.CharField(max_length=50)
@@ -385 +380 @@
 >>> p4.bachelorparty_set.all()
 [<BachelorParty: Bachelor party for Bob>, <BachelorParty: Bachelor party for Dave>]
 
-"""}
+# This works
+>>> Place.objects.exclude(restaurant=None)
+[<Place:  the place>]
 
+# ... and this doesn't.
+>>> Place.objects.filter(restaurant__isnull=False)
+[<Place:  the place>]
+"""}