[Answered ]-SQL – How do I create a linkage table?

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I think what you need is ForeignKey. You can link one Person object to another one. Just add this:

class Person(models.Model):
    ...
    agent = models.ForeignKey('self', on_delete=models.SET_NULL, null=True, related_name='clients')

From now on, you can simply add one Person as an agent in another Person‘s field. Usage:

person_1 = Person.objects.create(...)
person_2 = Person.objects.create(..., agent=person_1)

person_1.clients.all()
# <QuerySet [<Person: Person 2>]>

person_2 in person_1.clients.all()
# True

person_2.agent
# <Person: Person 1>

person_2.agent.related_entity.entity_type
# 'Company' / 'Person'

You can access related object by simple .agent or reverse relation of all clients with the related_name you want to use, in my example it’s .clients. Just remember, that reverse relation is always a QuerySet, because one agent can have many clients, but every client can have one agent. Relationhips are very powerful in Django, follow this DOCS for details.

👤NixonSparrow

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