Ticket #13815: 13815.patch

django/db/models/sql/query.py

@@ -1419 +1419 @@
         query.bump_prefix()
         query.clear_ordering(True)
         query.set_start(prefix)
+        # Adding extra check to make sure the selected field will not be null
+        # since we are adding a IN <subquery> clause. This prevents the
+        # database from tripping over IN (...,NULL,...) selects and returning
+        # nothing
+        alias, col = query.select[0]
+        query.where.add((Constraint(alias, col, None), 'isnull', False), AND)
+        # end of hack
         self.add_filter(('%s__in' % prefix, query), negate=True, trim=True,
                 can_reuse=can_reuse)
 

tests/regressiontests/null_queries/models.py

@@ -77 +77 @@
 >>> _ = Inner.objects.create(first=obj)
 >>> Inner.objects.filter(first__inner__second=None)
 [<Inner: Inner object>]
+>>> objB = OuterB.objects.create(data="reverse")
+>>> OuterB.objects.filter(inner__isnull=False)
+[]
+>>> _ = Inner.objects.create(first=obj)
+>>> OuterB.objects.exclude(inner__isnull=False)
+[<OuterB: OuterB object>]
 
-
 """}