Fixed #31382 -- Made Model.save(update_fields=...) raise ValueError on non-concrete fields.

django/db/models/base.py

@@ -727,7 +727,7 @@ class Model(metaclass=ModelBase):
             update_fields = frozenset(update_fields)
             field_names = set()
 
-            for field in self._meta.fields:
+            for field in self._meta.concrete_fields:
                 if not field.primary_key:
                     field_names.add(field.name)
 
@@ -737,9 +737,11 @@ class Model(metaclass=ModelBase):
             non_model_fields = update_fields.difference(field_names)
 
             if non_model_fields:
-                raise ValueError("The following fields do not exist in this "
+                raise ValueError(
-                                 "model or are m2m fields: %s"
+                    'The following fields do not exist in this model, are m2m '
-                                 % ', '.join(non_model_fields))
+                    'fields, or are non-concrete fields: %s'
+                    % ', '.join(non_model_fields)
+                )
 
         # If saving to the same database, and this model is deferred, then
         # automatically do an "update_fields" save on the loaded fields.

tests/update_only_fields/models.py

@@ -22,9 +22,19 @@ class Employee(Person):
     accounts = models.ManyToManyField('Account', related_name='employees', blank=True)
 
 
+class NonConcreteField(models.IntegerField):
+    def db_type(self, connection):
+        return None
+
+    def get_attname_column(self):
+        attname, _ = super().get_attname_column()
+        return attname, None
+
+
 class Profile(models.Model):
     name = models.CharField(max_length=200)
     salary = models.FloatField(default=1000.0)
+    non_concrete = NonConcreteField()
 
 
 class ProxyEmployee(Employee):

tests/update_only_fields/tests.py

@@ -5,7 +5,10 @@ from .models import Account, Employee, Person, Profile, ProxyEmployee
 
 
 class UpdateOnlyFieldsTests(TestCase):
-    msg = 'The following fields do not exist in this model or are m2m fields: %s'
+    msg = (
+        'The following fields do not exist in this model, are m2m fields, or '
+        'are non-concrete fields: %s'
+    )
 
     def test_update_fields_basic(self):
         s = Person.objects.create(name='Sara', gender='F')
@@ -254,3 +257,8 @@ class UpdateOnlyFieldsTests(TestCase):
         self.assertEqual(Person.objects.count(), 1)
         with self.assertNumQueries(2):
             s.save(update_fields=['name', 'employee_num'])
+
+    def test_update_non_concrete_field(self):
+        profile_boss = Profile.objects.create(name='Boss', salary=3000)
+        with self.assertRaisesMessage(ValueError, self.msg % 'non_concrete'):
+            profile_boss.save(update_fields=['non_concrete'])