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
36683	Update with Distinct Produces Unintentional Results	Matt Shirley	Matt Shirley	"Similar to #32433.

The ORM permits calling `update()` on a `Queryset` when a `distinct()` was applied. This results in unforeseen consequences where a larger data set will be updated than what is expected. Similar to the example provided in #32433:

`Comment.objects.order_by('post_id', 'created_at').distinct('post_id').update(deleted=True)`

The developer may assume that this will delete only one comment per `post_id`, however, the `distinct()` is ignored (as `UPDATE` has no distinct) which results in the entire table being updated:

`UPDATE ""post_comment"" SET ""deleted"" = true'`

Since `delete()` already guards against this case, I believe `update()` should behave consistently to protect the developer from mistakes, even though applying a `distinct()` before an `update()` is generally unusual."	Cleanup/optimization	closed	Database layer (models, ORM)	dev	Normal	fixed	orm,distinct,update		Ready for checkin	1	0	0	0	0	0