author | Nishanth Amuluru <nishanth@fossee.in> |
Sat, 08 Jan 2011 11:20:57 +0530 | |
changeset 69 | c6bca38c1cbf |
permissions | -rw-r--r-- |
69
c6bca38c1cbf
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Nishanth Amuluru <nishanth@fossee.in>
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""" |
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10. One-to-one relationships |
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Nishanth Amuluru <nishanth@fossee.in>
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To define a one-to-one relationship, use ``OneToOneField()``. |
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Nishanth Amuluru <nishanth@fossee.in>
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In this example, a ``Place`` optionally can be a ``Restaurant``. |
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Nishanth Amuluru <nishanth@fossee.in>
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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) |
c6bca38c1cbf
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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) |
c6bca38c1cbf
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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) |
c6bca38c1cbf
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Nishanth Amuluru <nishanth@fossee.in>
parents:
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class MultiModel(models.Model): |
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link1 = models.OneToOneField(Place) |
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parents:
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link2 = models.OneToOneField(ManualPrimaryKey) |
c6bca38c1cbf
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Nishanth Amuluru <nishanth@fossee.in>
parents:
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name = models.CharField(max_length=50) |
c6bca38c1cbf
Added buildout stuff and made changes accordingly
Nishanth Amuluru <nishanth@fossee.in>
parents:
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Nishanth Amuluru <nishanth@fossee.in>
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def __unicode__(self): |
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return u"Multimodel %s" % self.name |