53 lines
1.5 KiB
Python
53 lines
1.5 KiB
Python
"""
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33. get_or_create()
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get_or_create() does what it says: it tries to look up an object with the given
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parameters. If an object isn't found, it creates one with the given parameters.
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"""
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from django.db import models
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class Person(models.Model):
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first_name = models.CharField(max_length=100)
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last_name = models.CharField(max_length=100)
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birthday = models.DateField()
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def __unicode__(self):
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return u'%s %s' % (self.first_name, self.last_name)
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__test__ = {'API_TESTS':"""
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# Acting as a divine being, create an Person.
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>>> from datetime import date
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>>> p = Person(first_name='John', last_name='Lennon', birthday=date(1940, 10, 9))
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>>> p.save()
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# Only one Person is in the database at this point.
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>>> Person.objects.count()
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1
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# get_or_create() a person with similar first names.
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>>> p, created = Person.objects.get_or_create(first_name='John', last_name='Lennon', defaults={'birthday': date(1940, 10, 9)})
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# get_or_create() didn't have to create an object.
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>>> created
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False
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# There's still only one Person in the database.
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>>> Person.objects.count()
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1
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# get_or_create() a Person with a different name.
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>>> p, created = Person.objects.get_or_create(first_name='George', last_name='Harrison', defaults={'birthday': date(1943, 2, 25)})
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>>> created
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True
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>>> Person.objects.count()
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2
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# If we execute the exact same statement, it won't create a Person.
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>>> p, created = Person.objects.get_or_create(first_name='George', last_name='Harrison', defaults={'birthday': date(1943, 2, 25)})
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>>> created
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False
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>>> Person.objects.count()
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2
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"""}
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