#13815: Excluding isnull=False testing failing on reverse optional relations
------------------------------------------+---------------------------------
Reporter: bpeschier | Owner: nobody
Status: new | Milestone:
Component: Database layer (models, ORM) | Version: SVN
Keywords: isnull, reverse relation | Stage: Unreviewed
Has_patch: 0 |
------------------------------------------+---------------------------------
This one is related to #13768.
When executing {{{<queryset>.exclude(<reverse relation>__isnull=False)}}}
SQL is generated which can contain NULL-values in a subquery when the
relation is optional (null=True), always resulting in an empty resultset,
irregardless of other values in the subquery.
This is the SQL generated:
{{{
class Outer(models.Model):
name = models.CharField(max_length=1)
class Inner(models.Model):
outer = models.ForeignKey(Outer, null=True)
Outer.objects.exclude(inner__isnull=False):
SELECT "test_outer"."id", "test_outer"."name" FROM "test_outer" WHERE NOT
(("test_outer"."id" IN (SELECT U1."outer_id" FROM "test_inner" U1 WHERE
U1."id" IS NOT NULL) AND NOT ("test_outer"."id" IS NULL))) LIMIT 21
}}}
The subquery could include a test for the relation-field ({{{U1."outer_id"
IS NOT NULL}}}) to exclude unusable NULL-values, which will make this
work. SQL-generation in Django is one of the few areas I am not
comfortable with, so I have no relation to *where* to fix this.
I have attached a unittest to check all isnull-tests, just to be sure.
--
Ticket URL: <http://code.djangoproject.com/ticket/13815>
Django <http://code.djangoproject.com/>
The Web framework for perfectionists with deadlines.
--
You received this message because you are subscribed to the Google Groups
"Django updates" group.
To post to this group, send email to [email protected].
To unsubscribe from this group, send email to
[email protected].
For more options, visit this group at
http://groups.google.com/group/django-updates?hl=en.
