id	summary	reporter	owner	description	type	status	component	version	severity	resolution	keywords	cc	stage	has_patch	needs_docs	needs_tests	needs_better_patch	easy	ui_ux
12953	Generic-related objects are cascade-deleted, but the cascade does not extend beyond them	Carl Meyer	Carl Meyer	"Say I have these models:

{{{
class Award(models.Model):
    name = models.CharField(max_length=25)
    object_id = models.PositiveIntegerField()
    content_type = models.ForeignKey(ContentType)
    content_object = generic.GenericForeignKey()

class AwardNote(models.Model):
    award = models.ForeignKey(Award)
    note = models.CharField(max_length=100)

class Person(models.Model):
    name = models.CharField(max_length=25)
    awards = generic.GenericRelation(Award)
}}}

If I create one of each, then delete the Person, Django currently cascade-deletes the generically-related Award, but does not follow the relations any further, and thus the AwardNote is left undeleted. Databases which enforce referential integrity may delete the AwardNote themselves, or raise an error; databases which don't will leave the AwardNote with a broken ForeignKey.

Since Django's deletion behavior is advertised as equivalent to ON DELETE CASCADE, Django should explicitly delete the AwardNote in this case.

Currently deletion of generically-related objects is done in DeleteQuery.delete_batch_related(). I think the fix for this will involve moving it up to Model._collect_sub_objects() instead.

Testcase attached."		closed	Database layer (models, ORM)	dev		fixed		miracle2k	Accepted	1	0	0	0	0	0