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PODjango many-to-many relations, and through
 

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    <p>I want to store which user invited another user to a group... but django is telling me this is ambigous and against the rules (which makes sense). </p> <blockquote> <p>groups.group: Intermediary model Group_to_Member has more than one foreign key to User, which is ambiguous and is not permitted.</p> </blockquote> <p>So how do I do this correctly? Maybe a generic relation? might work but seems a bit convoluted... Here's how I was approaching it (with unrelated bits removed)</p> <pre><code>from django.contrib.auth.models import User class UserGroup(models.Model): members = models.ManyToManyField(User, through='Group_to_Member') class UserGroup_to_Member(models.Model): group = models.ForeignKey(UserGroup) member = models.ForeignKey(User) invited_by = models.ForeignKey(User, related_name="group_invited_users") </code></pre> <h2>Solution</h2> <p>Ok so I did a little combination of the answers you guys provided (Thanks!) and things I found on the internet plus my own admittedly meager python-fu:</p> <pre><code>from django.contrib.auth.models import User class UserGroup(models.Model): # notice there is no member object here ... other model data def add_member(self, **kwargs): g2m = UserGroup_to_Member(group = self, **kwargs) g2m.save() def remove_member(self, member): g2m = UserGroup_to_Member.objects.get(group=self, member=member) g2m.delete() # This is not elegant at all, help please? I'm pretty sure it isn't # as bad on the database as it looks though. def get_members(self): g2ms = UserGroup_to_Member.objects.filter(group=self) member_ids = [g2m.member.id for g2m in g2ms] members = User.objects.none() for id in member_ids: members = members | User.objects.get(id=id) return members class UserGroup_to_Member(models.Model): group = models.ForeignKey(UserGroup) member = models.ForeignKey(User) invited_by = models.ForeignKey(User, related_name="group_invited_users") </code></pre>
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    1. COThere's this previous answer: http://stackoverflow.com/questions/583327/django-model-with-2-foreign-keys-from-the-same-table
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    2. CO@seth, it's not a matter of adding a related_name, the issue is that there are 2 foreignkey relations to User, it doesn't matter what I call them or if I set a related_name
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    3. COThe other one had the exact same problem as you (i.e. 2 foreign keys on the same table) so I thought it would help. My django-fu is kind of raw though so perhaps I misunderstood your question. Do you have the DB set up? Why not just run inspectdb on it and see what models it generates? http://docs.djangoproject.com/en/dev/ref/django-admin/
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A row detail

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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