#32239: FilteredRelation is not working with GenericRelation
-------------------------------------+-------------------------------------
Reporter: Omar Altayyan | Owner: nobody
Type: Bug | Status: closed
Component: Database layer | Version: 3.1
(models, ORM) |
Severity: Normal | Resolution: needsinfo
Keywords: FilteredRelation | Triage Stage:
GenericRelation Generic Relation | Unreviewed
Has patch: 0 | Needs documentation: 0
Needs tests: 0 | Patch needs improvement: 0
Easy pickings: 0 | UI/UX: 0
-------------------------------------+-------------------------------------
Comment (by Ammar-Shiekh):
Here is the `test/models.py` file:
{{{
from django.db import models
class Workspace(models.Model):
pass
class Event(models.Model):
workspace = models.ForeignKey(Workspace, on_delete=models.CASCADE)
limit = models.FloatField(default=0)
entity_type = models.ForeignKey(ContentType, on_delete=models.CASCADE)
entity_id = models.PositiveIntegerField()
entity = GenericForeignKey('entity_type', 'entity_id')
class Entity(models.Model):
events = GenericRelation(Event, content_type_field='entity_type',
object_id_field='entity_id')
class Meta:
abstract = True
class SomeEntity(Entity):
pass
}}}
After migrating these models to the database, try running the following
code using `python manage.py shell`:
{{{
>>> from django.db.models import FilteredRelation
>>> from django.db.models.functions import Coalesce
>>> from test.models import SomeEntity
>>> str(SomeEntity.objects.annotate(
... workspace_events=FilteredRelation('events',
condition=Q(events__workspace_id=1)),
... limit=Coalesce('workspace_events__limit', 0),
... ).values('id', 'workspace_events__id',
'limit').order_by('-limit').query)
}}}
The last command will print this:
{{{
'SELECT "test_someentity"."id", workspace_events."id",
COALESCE(workspace_events."limit", 0) AS "limit" FROM "test_someentity"
LEFT OUTER JOIN "test_event" workspace_events ON ("test_someentity"."id" =
workspace_events."entity_id" AND (workspace_events."entity_type_id" =
186)) ORDER BY "limit" DESC'
}}}
Notice that the condition on events workspace id specified by the
FilteredRelation doesn't have an effect on the resulted query.
--
Ticket URL: <https://code.djangoproject.com/ticket/32239#comment:2>
Django <https://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 unsubscribe from this group and stop receiving emails from it, send an email
to django-updates+unsubscr...@googlegroups.com.
To view this discussion on the web visit
https://groups.google.com/d/msgid/django-updates/070.6d9da861ba5757ddb30d13773333848b%40djangoproject.com.
