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
31580	Expect to get SELECT DISTINCT ON after UNION of 2 annotated QuerySet	Sielc Technologies	nobody	"After using
- .annotate() on 2 different querysets
- and then .union()
- .distinct() will not affect the queryset

{{{
    def setUp(self) -> None:
        user = self.get_or_create_admin_user()

        Sample.h.create(user, name=""Sam1"")
        Sample.h.create(user, name=""Sam2 acid"")
        Sample.h.create(user, name=""Sam3"")
        Sample.h.create(user, name=""Sam4 acid"")

        Sample.h.create(user, name=""Dub"")
        Sample.h.create(user, name=""Dub"")
        Sample.h.create(user, name=""Dub"")

        self.user = user

    def test_union_annotated_diff_distinct(self):
        qs = Sample.objects.filter(user=self.user)
        qs1 = qs.filter(name='Dub').annotate(rank=Value(0, IntegerField()))
        qs2 = qs.filter(name='Sam1').annotate(rank=Value(1, IntegerField()))
        qs = qs1.union(qs2)
        qs = qs.order_by('name').distinct('name')  # THIS DISTINCT DONESN'T WORK
        self.assertEqual(qs.count(), 2)
}}}

expected to get wrapped union
{{{
    SELECT DISTINCT ON (siebox_sample.name) * FROM (SELECT ... UNION SELECT ...) AS siebox_sample
}}}
"	Bug	new	Database layer (models, ORM)	3.0	Normal		orm, distinct, annotate, union		Unreviewed	0	0	0	0	0	0