id	summary	reporter	owner	description	type	status	component	version	severity	resolution	keywords	cc	stage	has_patch	needs_docs	needs_tests	needs_better_patch	easy	ui_ux
34972	Aggregate with CombinedExpression resulting in NotImplemented instead of None after update from 3.2 -> 4.2	ElRoberto538	nobody	"Hi we're currently updating to Django 4.2 before 3.2 extended support ends, and have discovered a weird issue with some of our queries. Using 3.2 our simplified example query below would return None, now it returns NotImplemented, is this expected behavior? Shouldn't CombinedExpression have empty_result_set_value set to None to maintain existing behavior?


{{{
OurModel.objects.none().aggregate(random_aggregate=Sum('field_1')/Count('field_2'))['random_aggregate']
}}}
"	Bug	closed	Database layer (models, ORM)	4.2	Normal	worksforme	CombinedExpression, NotImplemented, aggregate	David Sanders	Unreviewed	0	0	0	0	0	0