加快Django .exists（）

Question

I have a query TranslationStep.objects.filter(step_id=pk) . I need to check if object is exist or not and if so, return object (or several objects). I have read that .exists() is more fastest way to do it, but I should make 2 requests.

if TranslationStep.objects.filter(step_id=pk).exists():
 return TranslationStep.objects.filter(step_id=pk)
else:
 return None

How can I optimise it?

Answer 1

You shouldn't do this at all. filter() will return an empty queryset if there is no match, which is False in a boolean context.