Fixed #36648, Refs #33772 -- Accounted for composite pks in first()/last() when aggregating.

Author: jacobtylerwalls

django/db/models/query.py

@@ -2141,8 +2141,14 @@ def _check_operator_queryset(self, other, operator_):
             raise TypeError(f"Cannot use {operator_} operator with combined queryset.")
 
     def _check_ordering_first_last_queryset_aggregation(self, method):
-        if isinstance(self.query.group_by, tuple) and not any(
-            col.output_field is self.model._meta.pk for col in self.query.group_by
+        if (
+            isinstance(self.query.group_by, tuple)
+            # Raise if the pk fields are not in the group_by.
+            and self.model._meta.pk
+            not in {col.output_field for col in self.query.group_by}
+            and set(self.model._meta.pk_fields).difference(
+                {col.target for col in self.query.group_by}
+            )
         ):
             raise TypeError(
                 f"Cannot use QuerySet.{method}() on an unordered queryset performing "

docs/releases/5.2.8.txt

@@ -10,3 +10,7 @@ Bugfixes
 ========
 
 * Added compatibility for ``oracledb`` 3.4.0 (:ticket:`36646`).
+
+* Fixed a bug in Django 5.2 where ``QuerySet.first()`` and ``QuerySet.last()``
+  raised an error on querysets performing aggregation that selected all fields
+  of a composite primary key.

tests/composite_pk/test_aggregate.py

@@ -141,3 +141,23 @@ def test_max_pk(self):
         msg = "Max expression does not support composite primary keys."
         with self.assertRaisesMessage(ValueError, msg):
             Comment.objects.aggregate(Max("pk"))
+
+    def test_first_from_unordered_queryset_aggregation_pk_selected(self):
+        self.assertEqual(
+            Comment.objects.values("pk").annotate(max=Max("id")).first(),
+            {"pk": (1, 1), "max": 1},
+        )
+
+    def test_first_from_unordered_queryset_aggregation_pk_selected_separately(self):
+        self.assertEqual(
+            Comment.objects.values("tenant", "id").annotate(max=Max("id")).first(),
+            {"tenant": 1, "id": 1, "max": 1},
+        )
+
+    def test_first_from_unordered_queryset_aggregation_pk_incomplete(self):
+        msg = (
+            "Cannot use QuerySet.first() on an unordered queryset performing "
+            "aggregation. Add an ordering with order_by()."
+        )
+        with self.assertRaisesMessage(TypeError, msg):
+            Comment.objects.values("tenant").annotate(max=Max("id")).first()