[1.9.x] Fixed #27342 -- Corrected QuerySet.update_or_create() example.

Backport of 51b83d9e51 from master
This commit is contained in:
Tim Graham 2016-10-13 11:02:02 -04:00
parent f0dd9dd72c
commit 9c956ff2f5
1 changed files with 8 additions and 4 deletions

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@ -1793,21 +1793,25 @@ the given ``kwargs``. If a match is found, it updates the fields passed in the
This is meant as a shortcut to boilerplatish code. For example::
defaults = {'first_name': 'Bob'}
try:
obj = Person.objects.get(first_name='John', last_name='Lennon')
for key, value in updated_values.iteritems():
for key, value in defaults.items():
setattr(obj, key, value)
obj.save()
except Person.DoesNotExist:
updated_values.update({'first_name': 'John', 'last_name': 'Lennon'})
obj = Person(**updated_values)
new_values = {'first_name': 'John', 'last_name': 'Lennon'}
new_values.update(defaults)
obj = Person(**new_values)
obj.save()
This pattern gets quite unwieldy as the number of fields in a model goes up.
The above example can be rewritten using ``update_or_create()`` like so::
obj, created = Person.objects.update_or_create(
first_name='John', last_name='Lennon', defaults=updated_values)
first_name='John', last_name='Lennon',
defaults={'first_name': 'Bob'},
)
For detailed description how names passed in ``kwargs`` are resolved see
:meth:`get_or_create`.