#31269: Generic Relations on multi table inheritance does not behave as other
               Reporter:  Eduardo Klein  |          Owner:  nobody
                   Type:  Uncategorized  |         Status:  new
              Component:  Uncategorized  |        Version:  3.0
               Severity:  Normal         |       Keywords:
           Triage Stage:  Unreviewed     |      Has patch:  0
    Needs documentation:  0              |    Needs tests:  0
Patch needs improvement:  0              |  Easy pickings:  0
                  UI/UX:  0              |
 Suppose we have the following models:

 class Tag(models.Model):
     content_type = models.ForeignKey('contenttypes.ContentType',
     object_id = models.PositiveIntegerField()
     obj = GenericForeignKey()

 class Point(models.Model):
     name = models.CharField(max_length=256)
     tags = GenericRelation("tag")

 class SpecificPoint(Point):

 We create a specific_point instance as follow:
 specific_point = SpecificPoint.objects.create(name="test")

 Now we add a tag to the corresponding point instance :
 point = Point.objects.get(pk=specific_point.id)
 tag = point.tags.create()

 When we do `specific_point.tags.all()` it returns en empty queryset,
 instead of a queryset containing the tag instance that we have created and
 that we would obtain doing `point.tags.all()`

 I understand that the issue here is that the content_type associated with
 the `tag` instance is the "point" one and not the "specificpoint", but
 it's problematic since if we do `specific_point.pk` or
 `specific_point.name` or any other field that is not a generic relation,
 we would obtain exactly the same as `point.pk` or `point.name`, but the
 "logic" is broken for generic relations.

 I'm not sure that this is a bug, but at least I think it deserves some
 consideration in the docs. If this is considered a bug, one possible
 solution would be to concatenate the tags from both models' content_types.

Ticket URL: <https://code.djangoproject.com/ticket/31269>
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