mirror of
https://github.com/django/django.git
synced 2024-12-25 10:35:48 +00:00
53 lines
1.5 KiB
Python
53 lines
1.5 KiB
Python
|
"""
|
||
|
32. get_or_create()
|
||
|
|
||
|
get_or_create() does what it says: it tries to look up an object with the given
|
||
|
parameters. If an object isn't found, it creates one with the given parameters.
|
||
|
"""
|
||
|
|
||
|
from django.db import models
|
||
|
|
||
|
class Person(models.Model):
|
||
|
first_name = models.CharField(maxlength=100)
|
||
|
last_name = models.CharField(maxlength=100)
|
||
|
birthday = models.DateField()
|
||
|
|
||
|
def __str__(self):
|
||
|
return '%s %s' % (self.first_name, self.last_name)
|
||
|
|
||
|
API_TESTS = """
|
||
|
# Acting as a divine being, create an Person.
|
||
|
>>> from datetime import date
|
||
|
>>> p = Person(first_name='John', last_name='Lennon', birthday=date(1940, 10, 9))
|
||
|
>>> p.save()
|
||
|
|
||
|
# Only one Person is in the database at this point.
|
||
|
>>> Person.objects.count()
|
||
|
1
|
||
|
|
||
|
# get_or_create() a person with similar first names.
|
||
|
>>> p, created = Person.objects.get_or_create(first_name='John', last_name='Lennon', defaults={'birthday': date(1940, 10, 9)})
|
||
|
|
||
|
# get_or_create() didn't have to create an object.
|
||
|
>>> created
|
||
|
False
|
||
|
|
||
|
# There's still only one Person in the database.
|
||
|
>>> Person.objects.count()
|
||
|
1
|
||
|
|
||
|
# get_or_create() a Person with a different name.
|
||
|
>>> p, created = Person.objects.get_or_create(first_name='George', last_name='Harrison', defaults={'birthday': date(1943, 2, 25)})
|
||
|
>>> created
|
||
|
True
|
||
|
>>> Person.objects.count()
|
||
|
2
|
||
|
|
||
|
# If we execute the exact same statement, it won't create a Person.
|
||
|
>>> p, created = Person.objects.get_or_create(first_name='George', last_name='Harrison', defaults={'birthday': date(1943, 2, 25)})
|
||
|
>>> created
|
||
|
False
|
||
|
>>> Person.objects.count()
|
||
|
2
|
||
|
"""
|