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Code Issues 32 Releases Wiki Activity

Refs #28312 -- Added an optimized __bool__() to ModelChoiceIterator.

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COUNT is more expensive than EXISTS; use the latter when possible.
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François Freitag
2018-04-13 18:39:10 -07:00
committed by Tim Graham
parent 3fca95e1ad
commit d1413c5d70
2 changed files with 14 additions and 0 deletions
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3
django/forms/models.py
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@@ -1145,6 +1145,9 @@ class ModelChoiceIterator:
# and __len__() won't be called.
return self.queryset.count() + (1 if self.field.empty_label is not None else 0)
def __bool__(self):
return self.field.empty_label is not None or self.queryset.exists()
def choice(self, obj):
return (self.field.prepare_value(obj), self.field.label_from_instance(obj))