Return to Snippet

Revision: 22994
at January 13, 2012 02:29 by magicrebirth


Updated Code
>>> ringo = Person.objects.create(name="Ringo Starr")
>>> paul = Person.objects.create(name="Paul McCartney")
>>> beatles = Group.objects.create(name="The Beatles")
>>> m1 = Membership(person=ringo, group=beatles,
...     date_joined=date(1962, 8, 16),
...     invite_reason= "Needed a new drummer.")
>>> m1.save()
>>> beatles.members.all()
[<Person: Ringo Starr>]
>>> ringo.group_set.all()
[<Group: The Beatles>]
>>> m2 = Membership.objects.create(person=paul, group=beatles,
...     date_joined=date(1960, 8, 1),
...     invite_reason= "Wanted to form a band.")
>>> beatles.members.all()
[<Person: Ringo Starr>, <Person: Paul McCartney>]

# Unlike normal many-to-many fields, you can't use add, create, or assignment (i.e., Beatles.members = [...]) to create relationships:


# THIS WILL NOT WORK
>>> beatles.members.add(john)
# NEITHER WILL THIS
>>> beatles.members.create(name="George Harrison")
# AND NEITHER WILL THIS
>>> beatles.members = [john, paul, ringo, george]

# Beatles have broken up
>>> beatles.members.clear()

Revision: 22993
at January 27, 2010 07:21 by magicrebirth


Initial Code
>>> ringo = Person.objects.create(name="Ringo Starr")
>>> paul = Person.objects.create(name="Paul McCartney")
>>> beatles = Group.objects.create(name="The Beatles")
>>> m1 = Membership(person=ringo, group=beatles,
...     date_joined=date(1962, 8, 16),
...     invite_reason= "Needed a new drummer.")
>>> m1.save()
>>> beatles.members.all()
[<Person: Ringo Starr>]
>>> ringo.group_set.all()
[<Group: The Beatles>]
>>> m2 = Membership.objects.create(person=paul, group=beatles,
...     date_joined=date(1960, 8, 1),
...     invite_reason= "Wanted to form a band.")
>>> beatles.members.all()
[<Person: Ringo Starr>, <Person: Paul McCartney>]

Initial URL
http://docs.djangoproject.com/en/1.1/topics/db/models/#extra-fields-on-many-to-many-relationships

Initial Description
Now that you have set up your ManyToManyField to use your intermediary model (Membership, in this case), you're ready to start creating some many-to-many relationships. You do this by creating instances of the intermediate model:

Initial Title
Django: instantiating M2M-through models

Initial Tags
django

Initial Language
Python