Opened 5 years ago

Last modified 5 years ago

#31580 closed Cleanup/optimization

Expect to get SELECT DISTINCT ON after UNION of 2 annotated QuerySet — at Version 1

Reported by: Sielc Technologies Owned by: nobody
Component: Database layer (models, ORM) Version: dev
Severity: Normal Keywords: orm, distinct, annotate, union
Cc: Hasan Ramezani Triage Stage: Ready for checkin
Has patch: yes Needs documentation: no
Needs tests: no Patch needs improvement: no
Easy pickings: yes UI/UX: no

Description (last modified by Sielc Technologies)

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 DOESN'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

Change History (1)

comment:1 by Sielc Technologies, 5 years ago

Description: modified (diff)
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