Commit 7bc57a6d authored by Anssi Kääriäinen's avatar Anssi Kääriäinen
Browse files

Fixed #11881 -- removed junk from aggregation subqueries 

There were clauses that weren't needed in the subqueries. These were
ORDER BY, SELECT FOR UPDATE and related selections.
parent 7737305a

django/db/models/sql/query.py

+9 −1
Original line number Diff line number Diff line
@@ -330,8 +330,16 @@ class Query(object): 
            from django.db.models.sql.subqueries import AggregateQuery

            query = AggregateQuery(self.model)

            obj = self.clone()

            relabels = dict((t, 'subquery') for t in self.tables)

            if not force_subq:

                # In forced subq case the ordering and limits will likely

                # affect the results.

                obj.clear_ordering(True)

                obj.clear_limits()

            obj.select_for_update = False

            obj.select_related = False

            obj.related_select_cols = []



            relabels = dict((t, 'subquery') for t in self.tables)

            # Remove any aggregates marked for reduction from the subquery

            # and move them to the outer AggregateQuery.

            for alias, aggregate in self.aggregate_select.items():

tests/aggregation/tests.py

+17 −0
Original line number Diff line number Diff line
@@ -3,8 +3,10 @@ from __future__ import unicode_literals 
import datetime

from decimal import Decimal



from django.db import connection

from django.db.models import Avg, Sum, Count, Max, Min

from django.test import TestCase, Approximate

from django.test.utils import CaptureQueriesContext



from .models import Author, Publisher, Book, Store
@@ -625,3 +627,18 @@ class BaseAggregateTestCase(TestCase): 
        qs = Book.objects.all().order_by('-rating')[0:3]

        vals = qs.aggregate(average_top3_rating=Avg('rating'))['average_top3_rating']

        self.assertAlmostEqual(vals, 4.5, places=2)



    def test_ticket11881(self):

        """

        Check that subqueries do not needlessly contain ORDER BY, SELECT FOR UPDATE

        or select_related() stuff.

        """

        qs = Book.objects.all().select_for_update().order_by(

            'pk').select_related('publisher').annotate(max_pk=Max('pk'))

        with CaptureQueriesContext(connection) as captured_queries:

            qs.aggregate(avg_pk=Avg('max_pk'))

            self.assertEqual(len(captured_queries), 1)

            qstr = captured_queries[0]['sql'].lower()

            self.assertNotIn('for update', qstr)

            self.assertNotIn('order by', qstr)

            self.assertEqual(qstr.count(' join '), 0)