Ticket #13203: 13203_r12773.diff

django/contrib/contenttypes/generic.py

@@ -123 +123 @@
         return smart_unicode([instance._get_pk_val() for instance in qs])
 
     def m2m_db_table(self):
-        return self.rel.to._meta.db_table
+        # check current model with all its parents for generic relation fields
+        model = self.rel.to
+        object_id_field = model._meta.get_field(self.object_id_field_name)
+        content_type_field = model._meta.get_field(self.content_type_field_name)
 
+        # get list with current model and all its parents
+        models = [model]
+        while True:
+            if model._meta.parents:
+                model = model._meta.parents.keys()[0]
+                models += [model]
+            else:
+                break
+
+        for model in models:
+            # check that both fields inside this model
+            if len(set(model._meta.local_fields) & set([object_id_field,content_type_field])) == 2:
+                return model._meta.db_table
+
+        raise Exception("Can't find model with '%s' and '%s' fields"
+            % (self.object_id_field_name, self.content_type_field_name))
+
     def m2m_column_name(self):
         return self.object_id_field_name