Fixed #24607 -- Serialized natural keys in multi-table inheritance models.

1 files changed, 6 insertions, 1 deletions

diff --git a/django/db/models/options.py b/django/db/models/options.py
index 0cf1726315..04696a4e9e 100644
--- a/django/db/models/options.py
+++ b/django/db/models/options.py
@@ -13,6 +13,7 @@ from django.db import connections
 from django.db.models import Manager
 from django.db.models.fields import AutoField
 from django.db.models.fields.proxy import OrderWrt
+from django.db.models.fields.related import OneToOneField
 from django.utils import six
 from django.utils.datastructures import ImmutableList, OrderedSet
 from django.utils.deprecation import (
@@ -296,7 +297,11 @@ class Options(object):
     def setup_pk(self, field):
         if not self.pk and field.primary_key:
             self.pk = field
-            field.serialize = False
+            # If the field is a OneToOneField and it's been marked as PK, then
+            # this is a multi-table inheritance PK. It needs to be serialized
+            # to relate the subclass instance to the superclass instance.
+            if not isinstance(field, OneToOneField):
+                field.serialize = False
 
     def setup_proxy(self, target):
         """