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    <p>Generic relationships and foreign keys are your friend in your path to succeed. Define an intermediate model where one side is generic, then the other side will get a related list of polymorphic models. It's just a little more complicated than a standard m2m join model, in that the generic side has two columns, one to ContentType (actually a FK) and the other to the PK of the actual linked model instance. You can also restrict the models to be linked with using standard FK parameters. You'll get used with it quickly. </p> <p>(now that I get an actual keyboard to write with, here there is the example:)</p> <pre><code>class Post(models.Model): class Meta: abstract = True CONCRETE_CLASSES = ('announcement', 'event',) removed_from = generic.GenericRelation('OwnerRemovedPost', content_type_field='content_type', object_id_field='post_id', ) class Announcement(Post): pass class Event(Post): pass class Owner(models.Model): # non-polymorphic m2m added_events = models.ManyToManyField(Event, null=True) # polymorphic m2m-like property def removed_posts(self): # can't use ManyToManyField with through. # can't return a QuerySet b/c it would be a union. return [i.post for i in self.removed_post_items.all()] def removed_events(self): # using Post's GenericRelation return Event.objects.filter(removed_from__owner=self) class OwnerRemovedPost(models.Model): content_type = models.ForeignKey(ContentType, limit_choices_to={'name__in': Post.CONCRETE_CLASSES}, ) post_id = models.PositiveIntegerField() post = generic.GenericForeignKey('content_type', 'post_id') owner = models.ForeignKey(Owner, related_name='removed_post_items') class Meta: unique_together = (('content_type', 'post_id'),) # to fake FK constraint </code></pre> <p>You can't filter into the related collection like a classic many-to-many, but with the proper methods in <code>Owner</code>, and using the concrete classes' managers smartly, you get everywhere you want.</p>
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    1. COWith a solution like that you might as well just the GenericForeignKey to the Announcement/Event on the model that needs the foreign key instead of using the intermediary.
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    2. CODepending on whether the original polymorphic modeling had a FK instead of a m2m, true. Anyway it's difficult to remove foreign keys when not needed anymore, much more than treat a m2m as a FK plus an inverse (soft) one to one. If the model is to be made sufficiently generic, it's either m2m or monkey patching, as in explicit field.contribute_to_class()...
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Detail views are divided into sections. All the information in the data section comes from columns in the selected row. The other sections display data from other, related rows.

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Try moving around until you find a non-empty to-many entry and click on the label to get to one. You can move back to the root by clicking on the database name in the header.

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