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"""
Many-to-many relationships between the same two tables
In this example, a ``Person`` can have many friends, who are also ``Person``
objects. Friendship is a symmetrical relationship - if I am your friend, you
are my friend. Here, ``friends`` is an example of a symmetrical
``ManyToManyField``.
A ``Person`` can also have many idols - but while I may idolize you, you may
not think the same of me. Here, ``idols`` is an example of a non-symmetrical
``ManyToManyField``. Only recursive ``ManyToManyField`` fields may be
non-symmetrical, and they are symmetrical by default.
This test validates that the many-to-many table is created using a mangled name
if there is a name clash, and tests that symmetry is preserved where
appropriate.
"""
from django.db import models
class Person(models.Model):
name = models.CharField(max_length=20)
friends = models.ManyToManyField('self')
colleagues = models.ManyToManyField('self', symmetrical=True, through='Colleague')
idols = models.ManyToManyField('self', symmetrical=False, related_name='stalkers')
def __str__(self):
return self.name
class Colleague(models.Model):
first = models.ForeignKey(Person, models.CASCADE)
second = models.ForeignKey(Person, models.CASCADE, related_name='+')
first_meet = models.DateField()
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