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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""" |
c6bca38c1cbf
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9. Many-to-many relationships via an intermediary table |
c6bca38c1cbf
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Nishanth Amuluru <nishanth@fossee.in>
parents:
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c6bca38c1cbf
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Nishanth Amuluru <nishanth@fossee.in>
parents:
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For many-to-many relationships that need extra fields on the intermediary |
c6bca38c1cbf
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Nishanth Amuluru <nishanth@fossee.in>
parents:
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table, use an intermediary model. |
c6bca38c1cbf
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Nishanth Amuluru <nishanth@fossee.in>
parents:
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c6bca38c1cbf
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Nishanth Amuluru <nishanth@fossee.in>
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In this example, an ``Article`` can have multiple ``Reporter`` objects, and |
c6bca38c1cbf
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Nishanth Amuluru <nishanth@fossee.in>
parents:
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each ``Article``-``Reporter`` combination (a ``Writer``) has a ``position`` |
c6bca38c1cbf
Added buildout stuff and made changes accordingly
Nishanth Amuluru <nishanth@fossee.in>
parents:
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field, which specifies the ``Reporter``'s position for the given article |
c6bca38c1cbf
Added buildout stuff and made changes accordingly
Nishanth Amuluru <nishanth@fossee.in>
parents:
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(e.g. "Staff writer"). |
c6bca38c1cbf
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Nishanth Amuluru <nishanth@fossee.in>
parents:
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""" |
c6bca38c1cbf
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Nishanth Amuluru <nishanth@fossee.in>
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c6bca38c1cbf
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from django.db import models |
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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) |
c6bca38c1cbf
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Nishanth Amuluru <nishanth@fossee.in>
parents:
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def __unicode__(self): |
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return u"%s %s" % (self.first_name, self.last_name) |
c6bca38c1cbf
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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 __unicode__(self): |
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return self.headline |
c6bca38c1cbf
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class Writer(models.Model): |
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reporter = models.ForeignKey(Reporter) |
c6bca38c1cbf
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parents:
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article = models.ForeignKey(Article) |
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parents:
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position = models.CharField(max_length=100) |
c6bca38c1cbf
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def __unicode__(self): |
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return u'%s (%s)' % (self.reporter, self.position) |
c6bca38c1cbf
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