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git-svn-id: http://code.djangoproject.com/svn/django/trunk@549 bcc190cf-cafb-0310-a4f2-bffc1f526a37
44 lines
1.4 KiB
Python
44 lines
1.4 KiB
Python
"""
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8. get_latest_by
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Models can have a ``get_latest_by`` attribute, which should be set to the name
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of a DateField or DateTimeField. If ``get_latest_by`` exists, the model's
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module will get a ``get_latest()`` function, which will return the latest
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object in the database according to that field. "Latest" means "having the
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date farthest into the future."
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"""
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from django.core import meta
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class Article(meta.Model):
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headline = meta.CharField(maxlength=100)
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pub_date = meta.DateTimeField()
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class META:
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get_latest_by = 'pub_date'
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def __repr__(self):
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return self.headline
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API_TESTS = """
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# Because no Articles exist yet, get_latest() raises ArticleDoesNotExist.
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>>> articles.get_latest()
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Traceback (most recent call last):
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...
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ArticleDoesNotExist: Article does not exist for {'order_by': ('-pub_date',), 'limit': 1}
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# Create a couple of Articles.
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>>> from datetime import datetime
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>>> a1 = articles.Article(id=None, headline='Article 1', pub_date=datetime(2005, 7, 26))
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>>> a1.save()
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>>> a2 = articles.Article(id=None, headline='Article 2', pub_date=datetime(2005, 7, 27))
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>>> a2.save()
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>>> a3 = articles.Article(id=None, headline='Article 3', pub_date=datetime(2005, 7, 27))
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>>> a3.save()
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>>> a4 = articles.Article(id=None, headline='Article 4', pub_date=datetime(2005, 7, 28))
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>>> a4.save()
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# Get the latest Article.
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>>> articles.get_latest()
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Article 4
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"""
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