44 lines
1.2 KiB
Python
44 lines
1.2 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.
|
|
|
|
Set ``related_name`` to designate what the reverse relationship is called.
|
|
"""
|
|
|
|
from django.db import models
|
|
|
|
class Person(models.Model):
|
|
full_name = models.CharField(maxlength=20)
|
|
mother = models.ForeignKey('self', null=True, related_name='mothers_child_set')
|
|
father = models.ForeignKey('self', null=True, related_name='fathers_child_set')
|
|
|
|
def __str__(self):
|
|
return self.full_name
|
|
|
|
__test__ = {'API_TESTS':"""
|
|
# Create two Person objects -- the mom and dad in our family.
|
|
>>> dad = Person(full_name='John Smith Senior', mother=None, father=None)
|
|
>>> dad.save()
|
|
>>> mom = Person(full_name='Jane Smith', mother=None, father=None)
|
|
>>> mom.save()
|
|
|
|
# Give mom and dad a kid.
|
|
>>> kid = Person(full_name='John Smith Junior', mother=mom, father=dad)
|
|
>>> kid.save()
|
|
|
|
>>> kid.mother
|
|
<Person: Jane Smith>
|
|
>>> kid.father
|
|
<Person: John Smith Senior>
|
|
>>> dad.fathers_child_set.all()
|
|
[<Person: John Smith Junior>]
|
|
>>> mom.mothers_child_set.all()
|
|
[<Person: John Smith Junior>]
|
|
>>> kid.mothers_child_set.all()
|
|
[]
|
|
>>> kid.fathers_child_set.all()
|
|
[]
|
|
"""}
|