Fixed empty strings + to_field regression on Oracle

Querying the reverse side of nullable to_field relation, where both
sides can contain null values resulted in incorrect results. The reason
was not detecting '' as NULL.

Refs #17541
This commit is contained in:
Anssi Kääriäinen 2013-02-23 00:00:41 +02:00
parent 60fff6fc94
commit 09fcb70c80
2 changed files with 4 additions and 3 deletions

View File

@ -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