mirror of
https://github.com/django/django.git
synced 2024-12-26 02:56:25 +00:00
52 lines
1.5 KiB
Python
52 lines
1.5 KiB
Python
|
"""
|
||
|
|
12. Relating a model to another model more than once
|
||
|
|
|
||
|
|
In this example, a ``Person`` can have a ``mother`` and ``father`` -- both of
|
||
|
|
which are other ``Person`` objects.
|
||
|
|
|
||
|
|
Because a ``Person`` has multiple relationships to ``Person``, we need to
|
||
|
|
distinguish the relationships. Set ``rel_name`` to tell Django what the
|
||
|
|
relationship should be called, because ``Person`` has two relationships to the
|
||
|
|
same model. Also, set ``related_name`` to designate what the reverse
|
||
|
|
relationship is called.
|
||
|
|
"""
|
||
|
|
|
||
|
|
from django.core import meta
|
||
|
|
|
||
|
|
class Person(meta.Model):
|
||
|
|
fields = (
|
||
|
|
meta.CharField('full_name', maxlength=20),
|
||
|
|
meta.ForeignKey('self', null=True, rel_name='mother',
|
||
|
|
related_name='mothers_child'),
|
||
|
|
meta.ForeignKey('self', null=True, rel_name='father',
|
||
|
|
related_name='fathers_child'),
|
||
|
|
)
|
||
|
|
|
||
|
|
def __repr__(self):
|
||
|
|
return self.full_name
|
||
|
|
|
||
|
|
API_TESTS = """
|
||
|
|
# Create two Person objects -- the mom and dad in our family.
|
||
|
|
>>> dad = persons.Person(id=None, full_name='John Smith Senior', mother_id=None, father_id=None)
|
||
|
|
>>> dad.save()
|
||
|
|
>>> mom = persons.Person(id=None, full_name='Jane Smith', mother_id=None, father_id=None)
|
||
|
|
>>> mom.save()
|
||
|
|
|
||
|
|
# Give mom and dad a kid.
|
||
|
|
>>> kid = persons.Person(id=None, full_name='John Smith Junior', mother_id=mom.id, father_id=dad.id)
|
||
|
|
>>> kid.save()
|
||
|
|
|
||
|
|
>>> kid.get_mother()
|
||
|
|
Jane Smith
|
||
|
|
>>> kid.get_father()
|
||
|
|
John Smith Senior
|
||
|
|
>>> dad.get_fathers_child_list()
|
||
|
|
[John Smith Junior]
|
||
|
|
>>> mom.get_mothers_child_list()
|
||
|
|
[John Smith Junior]
|
||
|
|
>>> kid.get_mothers_child_list()
|
||
|
|
[]
|
||
|
|
>>> kid.get_fathers_child_list()
|
||
|
|
[]
|
||
|
|
"""
|