diff --git a/tests/queries_/test_objectid.py b/tests/queries_/test_objectid.py
index effe6087..0d16540b 100644
--- a/tests/queries_/test_objectid.py
+++ b/tests/queries_/test_objectid.py
@@ -18,74 +18,77 @@ def setUpTestData(cls):
         cls.t4 = Tag.objects.create(name="t4", parent=cls.t3, group_id=cls.group_id_obj_2)
         cls.t5 = Tag.objects.create(name="t5", parent=cls.t3)
 
-    def test_filter_group_id_is_null(self):
+    def test_filter_group_id_is_null_false(self):
         """Filter objects where group_id is not null"""
-        for value, expected in [(False, [self.t3, self.t4]), (True, [self.t1, self.t2, self.t5])]:
-            with self.subTest(object_id=value):
-                qs = Tag.objects.filter(group_id__isnull=value).order_by("name")
-                self.assertSequenceEqual(qs, expected)
-
-    def test_filter_group_id_equal_value(self):
-        """Filter by group_id with a specific value"""
-        for value in [self.group_id_str_1, self.group_id_obj_1]:
-            with self.subTest(object_id=value):
-                qs = Tag.objects.filter(group_id=value).order_by("name")
-                self.assertSequenceEqual(qs, [self.t3])
-
-    def test_filter_group_id_in_value(self):
-        """Filter by group_id where value is in a list"""
-        test_cases = [
-            [self.group_id_str_1, self.group_id_str_2],
-            [self.group_id_obj_1, self.group_id_obj_2],
-        ]
-        for values in test_cases:
-            with self.subTest(values=values):
-                qs = Tag.objects.filter(group_id__in=values).order_by("name")
-                self.assertSequenceEqual(qs, [self.t3, self.t4])
+        qs = Tag.objects.filter(group_id__isnull=False).order_by("name")
+        self.assertSequenceEqual(qs, [self.t3, self.t4])
+
+    def test_filter_group_id_is_null_true(self):
+        """Filter objects where group_id is null"""
+        qs = Tag.objects.filter(group_id__isnull=True).order_by("name")
+        self.assertSequenceEqual(qs, [self.t1, self.t2, self.t5])
+
+    def test_filter_group_id_equal_str(self):
+        """Filter by group_id with a specific string value"""
+        qs = Tag.objects.filter(group_id=self.group_id_str_1).order_by("name")
+        self.assertSequenceEqual(qs, [self.t3])
+
+    def test_filter_group_id_equal_obj(self):
+        """Filter by group_id with a specific ObjectId value"""
+        qs = Tag.objects.filter(group_id=self.group_id_obj_1).order_by("name")
+        self.assertSequenceEqual(qs, [self.t3])
+
+    def test_filter_group_id_in_str_values(self):
+        """Filter by group_id with string values in a list"""
+        qs = Tag.objects.filter(group_id__in=[self.group_id_str_1, self.group_id_str_2]).order_by(
+            "name"
+        )
+        self.assertSequenceEqual(qs, [self.t3, self.t4])
+
+    def test_filter_group_id_in_obj_values(self):
+        """Filter by group_id with ObjectId values in a list"""
+        qs = Tag.objects.filter(group_id__in=[self.group_id_obj_1, self.group_id_obj_2]).order_by(
+            "name"
+        )
+        self.assertSequenceEqual(qs, [self.t3, self.t4])
 
     def test_filter_group_id_equal_subquery(self):
         """Filter by group_id using a subquery"""
         subquery = Tag.objects.filter(name="t3").values("group_id")
-        for value in [self.group_id_str_1, self.group_id_obj_1]:
-            with self.subTest(object_id=value):
-                qs = Tag.objects.filter(group_id__in=subquery).order_by("name")
-                self.assertSequenceEqual(qs, [self.t3])
+        qs = Tag.objects.filter(group_id__in=subquery).order_by("name")
+        self.assertSequenceEqual(qs, [self.t3])
 
     def test_filter_group_id_in_subquery(self):
         """Filter by group_id using a subquery with multiple values"""
         subquery = Tag.objects.filter(name__in=["t3", "t4"]).values("group_id")
-        test_cases = [
-            [self.group_id_str_1, self.group_id_str_2],
-            [self.group_id_obj_1, self.group_id_obj_2],
-        ]
-        for values in test_cases:
-            with self.subTest(values=values):
-                qs = Tag.objects.filter(group_id__in=subquery).order_by("name")
-                self.assertSequenceEqual(qs, [self.t3, self.t4])
-
-    def test_filter_parent_by_children_values(self):
-        """Query to select parents of children based on group_id"""
-        child_group_ids = [self.group_id_str_1, self.group_id_obj_1]
-        for group_id in child_group_ids:
-            with self.subTest(group_id=group_id):
-                child_ids = Tag.objects.filter(group_id=group_id).values_list("id", flat=True)
-                parent_qs = (
-                    Tag.objects.filter(children__id__in=child_ids).distinct().order_by("name")
-                )
-                self.assertSequenceEqual(parent_qs, [self.t1])
-
-    def test_filter_group_id_union_with(self):
-        """Combine queries using union"""
-        test_cases = [
-            (self.group_id_str_1, self.group_id_str_2),
-            (self.group_id_obj_1, self.group_id_obj_2),
-        ]
-        for value1, value2 in test_cases:
-            with self.subTest(value1=value1, value2=value2):
-                qs_a = Tag.objects.filter(group_id=value1)
-                qs_b = Tag.objects.filter(group_id=value2)
-                union_qs = qs_a.union(qs_b).order_by("name")
-                self.assertSequenceEqual(union_qs, [self.t3, self.t4])
+        qs = Tag.objects.filter(group_id__in=subquery).order_by("name")
+        self.assertSequenceEqual(qs, [self.t3, self.t4])
+
+    def test_filter_parent_by_children_values_str(self):
+        """Query to select parents of children with specific string group_id"""
+        child_ids = Tag.objects.filter(group_id=self.group_id_str_1).values_list("id", flat=True)
+        parent_qs = Tag.objects.filter(children__id__in=child_ids).distinct().order_by("name")
+        self.assertSequenceEqual(parent_qs, [self.t1])
+
+    def test_filter_parent_by_children_values_obj(self):
+        """Query to select parents of children with specific ObjectId group_id"""
+        child_ids = Tag.objects.filter(group_id=self.group_id_obj_1).values_list("id", flat=True)
+        parent_qs = Tag.objects.filter(children__id__in=child_ids).distinct().order_by("name")
+        self.assertSequenceEqual(parent_qs, [self.t1])
+
+    def test_filter_group_id_union_with_str(self):
+        """Combine queries using union with string values"""
+        qs_a = Tag.objects.filter(group_id=self.group_id_str_1)
+        qs_b = Tag.objects.filter(group_id=self.group_id_str_2)
+        union_qs = qs_a.union(qs_b).order_by("name")
+        self.assertSequenceEqual(union_qs, [self.t3, self.t4])
+
+    def test_filter_group_id_union_with_obj(self):
+        """Combine queries using union with ObjectId values"""
+        qs_a = Tag.objects.filter(group_id=self.group_id_obj_1)
+        qs_b = Tag.objects.filter(group_id=self.group_id_obj_2)
+        union_qs = qs_a.union(qs_b).order_by("name")
+        self.assertSequenceEqual(union_qs, [self.t3, self.t4])
 
     def test_invalid_object_id(self):
         """Test invalid value in filter"""