mirror of https://github.com/django/django.git
74 lines
1.9 KiB
Python
74 lines
1.9 KiB
Python
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"""
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4. Many-to-one relationships
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To define a many-to-one relationship, use ForeignKey().
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"""
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from django.core import meta
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class Reporter(meta.Model):
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fields = (
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meta.CharField('first_name', maxlength=30),
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meta.CharField('last_name', maxlength=30),
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)
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def __repr__(self):
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return "%s %s" % (self.first_name, self.last_name)
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class Article(meta.Model):
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fields = (
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meta.CharField('headline', maxlength=100),
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meta.DateField('pub_date'),
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meta.ForeignKey(Reporter),
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)
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def __repr__(self):
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return self.headline
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API_TESTS = """
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# Create a Reporter.
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>>> r = reporters.Reporter(id=None, first_name='John', last_name='Smith')
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>>> r.save()
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# Create an Article.
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>>> from datetime import datetime
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>>> a = articles.Article(id=None, headline='This is a test', pub_date=datetime(2005, 7, 27), reporter_id=r.id)
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>>> a.save()
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>>> a.reporter_id
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1L
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>>> a.get_reporter()
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John Smith
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# Article objects have access to their related Reporter objects.
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>>> r = a.get_reporter()
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>>> r.first_name, r.last_name
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('John', 'Smith')
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# Create an Article via the Reporter object.
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>>> new_article = r.add_article(headline="John's second story", pub_date=datetime(2005, 7, 28))
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>>> new_article
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John's second story
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>>> new_article.reporter_id
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1
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# Reporter objects have access to their related Article objects.
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>>> r.get_article_list(order_by=['pub_date'])
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[This is a test, John's second story]
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>>> r.get_article(headline__startswith='This')
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This is a test
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>>> r.get_article_count()
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2L
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# The API automatically follows relationships as far as you need.
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# Use double underscores to separate relationships.
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# This works as many levels deep as you want. There's no limit.
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# Find all Articles for any Reporter whose first name is "John".
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>>> articles.get_list(reporter__first_name__exact='John', order_by=['pub_date'])
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[This is a test, John's second story]
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"""
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