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36 lines
810 B
36 lines
810 B
13 years ago
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"""
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24. Mutually referential many-to-one relationships
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Strings can be used instead of model literals to set up "lazy" relations.
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"""
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from django.db.models import *
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class Parent(Model):
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name = CharField(max_length=100)
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# Use a simple string for forward declarations.
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bestchild = ForeignKey("Child", null=True, related_name="favoured_by")
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class Child(Model):
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name = CharField(max_length=100)
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# You can also explicitally specify the related app.
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parent = ForeignKey("mutually_referential.Parent")
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__test__ = {'API_TESTS':"""
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# Create a Parent
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>>> q = Parent(name='Elizabeth')
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>>> q.save()
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# Create some children
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>>> c = q.child_set.create(name='Charles')
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>>> e = q.child_set.create(name='Edward')
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# Set the best child
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>>> q.bestchild = c
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>>> q.save()
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>>> q.delete()
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"""}
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