diff --git a/django/db/models/fields/related.py b/django/db/models/fields/related.py index 804dda5817..bea88ba337 100644 --- a/django/db/models/fields/related.py +++ b/django/db/models/fields/related.py @@ -1,6 +1,6 @@ from operator import attrgetter -from django.db import connection, router +from django.db import connection, connections, router from django.db.backends import util from django.db.models import signals, get_model from django.db.models.fields import (AutoField, Field, IntegerField, @@ -496,7 +496,8 @@ class ForeignRelatedObjectsDescriptor(object): except (AttributeError, KeyError): db = self._db or router.db_for_read(self.model, instance=self.instance) qs = super(RelatedManager, self).get_query_set().using(db).filter(**self.core_filters) - if getattr(self.instance, attname) is None: + val = getattr(self.instance, attname) + if val is None or val == '' and connections[db].features.interprets_empty_strings_as_nulls: return qs.none() qs._known_related_objects = {rel_field: {self.instance.pk: self.instance}} return qs diff --git a/tests/regressiontests/many_to_one_regress/tests.py b/tests/regressiontests/many_to_one_regress/tests.py index e140577a49..a9969a7e90 100644 --- a/tests/regressiontests/many_to_one_regress/tests.py +++ b/tests/regressiontests/many_to_one_regress/tests.py @@ -126,7 +126,7 @@ class ManyToOneRegressionTests(TestCase): # Now the model is saved, so we will need to execute an query. with self.assertNumQueries(1): self.assertEqual(th.child_set.count(), 0) - + def test_related_null_to_field(self): c1 = Car.objects.create() c2 = Car.objects.create()