Commit 2aa2b9f2 authored by Paweł Marczewski's avatar Paweł Marczewski Committed by Tim Graham
Browse files

[1.8.x] Fixed #24835 -- Fixed QuerySet.exists() after an annotation with Count() 

QuerySet.exists() incorrectly handled query.group_by = True
case (grouping by all select fields), causing GROUP BY
expressions to be wiped along with select fields.

Backport of 801a84ae from master
parent 1ac4c7d4

django/db/models/sql/query.py

+3 −0
Original line number Diff line number Diff line
@@ -472,6 +472,9 @@ class Query(object): 
    def has_results(self, using):

        q = self.clone()

        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()

            q.clear_select_clause()

        q.clear_ordering(True)

        q.set_limits(high=1)

docs/releases/1.8.3.txt

+3 −0
Original line number Diff line number Diff line
@@ -14,3 +14,6 @@ Bugfixes 


* Fixed crash during :djadmin:`makemigrations` if a migrations module either

  is missing ``__init__.py`` or is a file (:ticket:`24848`).



* Fixed ``exists()`` returning incorrect results after annotation with

  ``Count()`` (:ticket:`24835`).

tests/annotations/tests.py

+4 −0
Original line number Diff line number Diff line
@@ -245,6 +245,10 @@ class NonAggregateAnnotationTestCase(TestCase): 
            lambda a: (a['age'], a['age_count'])

        )



    def test_annotate_exists(self):

        authors = Author.objects.annotate(c=Count('id')).filter(c__gt=1)

        self.assertFalse(authors.exists())



    def test_column_field_ordering(self):

        """

        Test that columns are aligned in the correct order for