id	summary	reporter	owner	description	type	status	component	version	severity	resolution	keywords	cc	stage	has_patch	needs_docs	needs_tests	needs_better_patch	easy	ui_ux
36181	Composite primary key fields cannot use __in lookup with explicit Subquery	Jacob Walls	Simon Charette	"In a recent PR, we [https://github.com/django/django/pull/19108#discussion_r1932339414 surfaced] some inconsistencies with the resolution of explicit `Subquery()` such that some lookups might fail:

{{{#!diff
diff --git a/tests/composite_pk/test_filter.py b/tests/composite_pk/test_filter.py
index 937dd86652..60d43f4a52 100644
--- a/tests/composite_pk/test_filter.py
+++ b/tests/composite_pk/test_filter.py
@@ -437,6 +437,11 @@ class CompositePKFilterTests(TestCase):
         queryset = User.objects.filter(comments__in=subquery)
         self.assertSequenceEqual(queryset, (self.user_2,))
 
+    def test_explicit_subquery(self):
+        subquery = Subquery(User.objects.values(""pk""))
+        self.assertEqual(User.objects.filter(pk__in=subquery).count(), 5)
+        self.assertEqual(Comment.objects.filter(user__in=subquery).count(), 5)
+
     def test_cannot_cast_pk(self):
         msg = ""Cast expression does not support composite primary keys.""
         with self.assertRaisesMessage(ValueError, msg):
}}}

gives
{{{#!py
======================================================================
ERROR: test_explicit_subquery (composite_pk.test_filter.CompositePKFilterTests.test_explicit_subquery)
----------------------------------------------------------------------
Traceback (most recent call last):
  File ""/Users/.../django/tests/composite_pk/test_filter.py"", line 418, in test_explicit_subquery
    self.assertEqual(Comment.objects.filter(user__in=subquery).count(), 5)
                     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File ""/Users/.../django/django/db/models/query.py"", line 603, in count
    return self.query.get_count(using=self.db)
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File ""/Users/.../django/django/db/models/sql/query.py"", line 644, in get_count
    return obj.get_aggregation(using, {""__count"": Count(""*"")})[""__count""]
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File ""/Users/.../django/django/db/models/sql/query.py"", line 626, in get_aggregation
    result = compiler.execute_sql(SINGLE)
             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File ""/Users/.../django/django/db/models/sql/compiler.py"", line 1610, in execute_sql
    sql, params = self.as_sql()
                  ^^^^^^^^^^^^^
  File ""/Users/.../django/django/db/models/sql/compiler.py"", line 794, in as_sql
    self.compile(self.where) if self.where is not None else ("""", [])
    ^^^^^^^^^^^^^^^^^^^^^^^^
  File ""/Users/.../django/django/db/models/sql/compiler.py"", line 577, in compile
    sql, params = node.as_sql(self, self.connection)
                  ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File ""/Users/.../django/django/db/models/sql/where.py"", line 151, in as_sql
    sql, params = compiler.compile(child)
                  ^^^^^^^^^^^^^^^^^^^^^^^
  File ""/Users/.../django/django/db/models/sql/compiler.py"", line 577, in compile
    sql, params = node.as_sql(self, self.connection)
                  ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File ""/Users/.../django/django/db/models/fields/related_lookups.py"", line 86, in as_sql
    SubqueryConstraint(
  File ""/Users/.../django/django/db/models/sql/where.py"", line 358, in __init__
    query_object.clear_ordering(clear_default=True)
    ^^^^^^^^^^^^^^^^^^^^^^^^^^^
AttributeError: 'Subquery' object has no attribute 'clear_ordering'
}}}"	Bug	closed	Database layer (models, ORM)	5.2	Release blocker	fixed			Ready for checkin	1	0	0	0	0	0