Fixed #24924 -- Join promotion for multiple Case expressions (541f4ea5) · Commits · Dom Sekotill / django

django/db/models/query_utils.py

+1 −3

Original line number	Diff line number	Diff line
		@@ -89,10 +89,8 @@ class Q(tree.Node):
		def resolve_expression(self, query=None, allow_joins=True, reuse=None, summarize=False, for_save=False):
		# We must promote any new joins to left outer joins so that when Q is
		# used as an expression, rows aren't filtered due to joins.
		joins_before = query.tables[:]
		clause, joins = query._add_q(self, reuse, allow_joins=allow_joins, split_subq=False)
		joins_to_promote = [j for j in joins if j not in joins_before]
		query.promote_joins(joins_to_promote)
		query.promote_joins(joins)
		return clause

		@classmethod

+4 −0

Original line number	Diff line number	Diff line
		@@ -53,3 +53,7 @@ Bugfixes

		* Fixed queryset annotations when using ``Case`` expressions with ``exclude()``
		(:ticket:`24833`).

		* Corrected join promotion for multiple ``Case`` expressions. Annotating a
		query with multiple ``Case`` expressions could unexpectedly filter out
		results (:ticket:`24924`).

+42 −0

Original line number	Diff line number	Diff line
		@@ -1060,6 +1060,48 @@ class CaseExpressionTests(TestCase):
		lambda x: (x, x.foo)
		)

		def test_join_promotion_multiple_annonations(self):
		o = CaseTestModel.objects.create(integer=1, integer2=1, string='1')
		# Testing that:
		# 1. There isn't any object on the remote side of the fk_rel
		# relation. If the query used inner joins, then the join to fk_rel
		# would remove o from the results. So, in effect we are testing that
		# we are promoting the fk_rel join to a left outer join here.
		# 2. The default value of 3 is generated for the case expression.
		self.assertQuerysetEqual(
		CaseTestModel.objects.filter(pk=o.pk).annotate(
		foo=Case(
		When(fk_rel__pk=1, then=2),
		default=3,
		output_field=models.IntegerField()
		),
		bar=Case(
		When(fk_rel__pk=1, then=4),
		default=5,
		output_field=models.IntegerField()
		),
		),
		[(o, 3, 5)],
		lambda x: (x, x.foo, x.bar)
		)
		# Now 2 should be generated, as the fk_rel is null.
		self.assertQuerysetEqual(
		CaseTestModel.objects.filter(pk=o.pk).annotate(
		foo=Case(
		When(fk_rel__isnull=True, then=2),
		default=3,
		output_field=models.IntegerField()
		),
		bar=Case(
		When(fk_rel__isnull=True, then=4),
		default=5,
		output_field=models.IntegerField()
		),
		),
		[(o, 2, 4)],
		lambda x: (x, x.foo, x.bar)
		)

		def test_m2m_exclude(self):
		CaseTestModel.objects.create(integer=10, integer2=1, string='1')
		qs = CaseTestModel.objects.values_list('id', 'integer').annotate(