Fixed #31109 -- Disabled grouping by aliases on QuerySet.exists().

Clearing the SELECT clause in Query.has_results was orphaning GROUP BY
references to it.

Thanks Thierry Bastian for the report and Baptiste Mispelon for the
bisect.

Regression in fb3f034f1c.
This commit is contained in:
Simon Charette 2019-12-21 23:22:49 -05:00 committed by Mariusz Felisiak
parent cebd41e416
commit 720de4d044
3 changed files with 19 additions and 2 deletions

View File

@ -526,7 +526,9 @@ class Query(BaseExpression):
if not q.distinct:
if q.group_by is True:
q.add_fields((f.attname for f in self.model._meta.concrete_fields), False)
q.set_group_by()
# Disable GROUP BY aliases to avoid orphaning references to the
# SELECT clause which is about to be cleared.
q.set_group_by(allow_aliases=False)
q.clear_select_clause()
q.clear_ordering(True)
q.set_limits(high=1)
@ -1916,7 +1918,7 @@ class Query(BaseExpression):
if force_empty:
self.default_ordering = False
def set_group_by(self):
def set_group_by(self, allow_aliases=True):
"""
Expand the GROUP BY clause required by the query.
@ -1938,6 +1940,8 @@ class Query(BaseExpression):
warnings.warn(msg, category=RemovedInDjango40Warning)
group_by_cols = annotation.get_group_by_cols()
else:
if not allow_aliases:
alias = None
group_by_cols = annotation.get_group_by_cols(alias=alias)
group_by.extend(group_by_cols)
self.group_by = tuple(group_by)

View File

@ -11,3 +11,6 @@ Bugfixes
* Fixed a regression in Django 3.0 that didn't include columns referenced by a
``Subquery()`` in the ``GROUP BY`` clause (:ticket:`31094`).
* Fixed a regression in Django 3.0 where ``QuerySet.exists()`` crashed if a
queryset contained an aggregation over a ``Subquery()`` (:ticket:`31109`).

View File

@ -1141,6 +1141,16 @@ class AggregateTestCase(TestCase):
# The GROUP BY should not be by alias either.
self.assertEqual(ctx[0]['sql'].lower().count('latest_book_pubdate'), 1)
def test_aggregation_subquery_annotation_exists(self):
latest_book_pubdate_qs = Book.objects.filter(
publisher=OuterRef('pk')
).order_by('-pubdate').values('pubdate')[:1]
publisher_qs = Publisher.objects.annotate(
latest_book_pubdate=Subquery(latest_book_pubdate_qs),
count=Count('book'),
)
self.assertTrue(publisher_qs.exists())
@skipUnlessDBFeature('supports_subqueries_in_group_by')
def test_group_by_subquery_annotation(self):
"""