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"""
10. One-to-one relationships
To define a one-to-one relationship, use ``OneToOneField()``.
In this example, a ``Place`` optionally can be a ``Restaurant``.
"""
from django.db import models
class Place(models.Model):
name = models.CharField(max_length=50)
address = models.CharField(max_length=80)
def __unicode__(self):
return u"%s the place" % self.name
class Restaurant(models.Model):
place = models.OneToOneField(Place, primary_key=True)
serves_hot_dogs = models.BooleanField()
serves_pizza = models.BooleanField()
def __unicode__(self):
return u"%s the restaurant" % self.place.name
class Waiter(models.Model):
restaurant = models.ForeignKey(Restaurant)
name = models.CharField(max_length=50)
def __unicode__(self):
return u"%s the waiter at %s" % (self.name, self.restaurant)
class ManualPrimaryKey(models.Model):
primary_key = models.CharField(max_length=10, primary_key=True)
name = models.CharField(max_length = 50)
class RelatedModel(models.Model):
link = models.OneToOneField(ManualPrimaryKey)
name = models.CharField(max_length = 50)
class MultiModel(models.Model):
link1 = models.OneToOneField(Place)
link2 = models.OneToOneField(ManualPrimaryKey)
name = models.CharField(max_length=50)
def __unicode__(self):
return u"Multimodel %s" % self.name
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