Fixed #28107 -- Added DatabaseFeatures.allows_group_by_selected_pks_on_model() to allow enabling optimization for unmanaged models.

1 files changed, 27 insertions, 0 deletions

diff --git a/tests/aggregation_regress/tests.py b/tests/aggregation_regress/tests.py
index 4142643020..6234d3c590 100644
--- a/tests/aggregation_regress/tests.py
+++ b/tests/aggregation_regress/tests.py
@@ -1333,6 +1333,33 @@ class AggregationTests(TestCase):
                 self.assertIn(field.name, grouping[index + 1][0])
             assertQuerysetResults(queryset)
 
+    @skipUnlessDBFeature('allows_group_by_selected_pks')
+    def test_aggregate_unmanaged_model_as_tables(self):
+        qs = Book.objects.select_related('contact').annotate(num_authors=Count('authors'))
+        # Force treating unmanaged models as tables.
+        with mock.patch(
+            'django.db.connection.features.allows_group_by_selected_pks_on_model',
+            return_value=True,
+        ):
+            with mock.patch.object(Book._meta, 'managed', False), \
+                    mock.patch.object(Author._meta, 'managed', False):
+                _, _, grouping = qs.query.get_compiler(using='default').pre_sql_setup()
+                self.assertEqual(len(grouping), 2)
+                self.assertIn('id', grouping[0][0])
+                self.assertIn('id', grouping[1][0])
+                self.assertQuerysetEqual(
+                    qs.order_by('name'),
+                    [
+                        ('Artificial Intelligence: A Modern Approach', 2),
+                        ('Paradigms of Artificial Intelligence Programming: Case Studies in Common Lisp', 1),
+                        ('Practical Django Projects', 1),
+                        ('Python Web Development with Django', 3),
+                        ('Sams Teach Yourself Django in 24 Hours', 1),
+                        ('The Definitive Guide to Django: Web Development Done Right', 2),
+                    ],
+                    attrgetter('name', 'num_authors'),
+                )
+
     def test_reverse_join_trimming(self):
         qs = Author.objects.annotate(Count('book_contact_set__contact'))
         self.assertIn(' JOIN ', str(qs.query))