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