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For those relationships, you simply connect the appropriate fields with a line. To create many-to-many relationships, you need to create a new table to connect the other two. This new table is called an intermediate table (or sometimes a linking or junction table).
Behind the scenes, Django creates an intermediary join table to represent the many-to-many relationship. By default, this table name is generated using the name of the many-to-many field and the name of the table for the model that contains it.
Use: object.m2mfield.add(*items) as described in the documentation:
add() accepts an arbitrary number of arguments, not a list of them.
add(obj1, obj2, obj3, ...)
To expand that list into arguments, use *
add(*[obj1, obj2, obj3])
Django does not call obj.save() for each item but uses bulk_create(), instead.
To add on, If you want to add them from a queryset
Example
# Returns a queryset
permissions = Permission.objects.all()
# Add the results to the many to many field (notice the *)
group = MyGroup.objects.get(name='test')
group.permissions.add(*permissions)
From: Insert queryset results into ManytoManyfield
Django 1.9 adds additional ways for adding to a many-to-many relationship.
Documentation: https://docs.djangoproject.com/en/dev/ref/models/relations/#django.db.models.fields.related.RelatedManager.set
set is a new nicety:
>>> new_list = [obj1, obj2, obj3]
>>> e.related_set.set(new_list)
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