42 lines
1.2 KiB
Python
42 lines
1.2 KiB
Python
"""
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9. Many-to-many relationships via an intermediary table
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For many-to-many relationships that need extra fields on the intermediary
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table, use an intermediary model.
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In this example, an ``Article`` can have multiple ``Reporter`` objects, and
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each ``Article``-``Reporter`` combination (a ``Writer``) has a ``position``
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field, which specifies the ``Reporter``'s position for the given article
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(e.g. "Staff writer").
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"""
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from __future__ import unicode_literals
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from django.db import models
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from django.utils.encoding import python_2_unicode_compatible
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@python_2_unicode_compatible
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class Reporter(models.Model):
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first_name = models.CharField(max_length=30)
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last_name = models.CharField(max_length=30)
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def __str__(self):
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return "%s %s" % (self.first_name, self.last_name)
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@python_2_unicode_compatible
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class Article(models.Model):
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headline = models.CharField(max_length=100)
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pub_date = models.DateField()
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def __str__(self):
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return self.headline
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@python_2_unicode_compatible
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class Writer(models.Model):
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reporter = models.ForeignKey(Reporter)
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article = models.ForeignKey(Article)
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position = models.CharField(max_length=100)
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def __str__(self):
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return '%s (%s)' % (self.reporter, self.position)
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