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
27995	Raise a descriptive error on unsupported operations following QuerySet.union(), intersection(), and difference().	Tim Graham	Hasan Ramezani	"The documentation for `QuerySet.union()` says, ""In addition, only LIMIT, OFFSET, and ORDER BY (i.e. slicing and order_by()) are allowed on the resulting QuerySet."", however, there isn't any strict enforcement about this -- some operations like `QuerySet.count()` might appear to work. See #27982 and #27990 for confusion about this."	Cleanup/optimization	closed	Database layer (models, ORM)	dev	Normal	fixed			Accepted	1	0	0	0	0	0