Refs #14357 -- Deprecated Meta.ordering affecting GROUP BY queries.

Thanks Ramiro Morales for contributing to the patch.
This commit is contained in:
Ramiro Morales 2018-09-13 13:29:48 -03:00 committed by Tim Graham
parent c52ecbda61
commit 1b1f64ee5a
9 changed files with 80 additions and 16 deletions

View File

@ -14,7 +14,9 @@ from django.db.models.sql.constants import (
from django.db.models.sql.query import Query, get_order_dir
from django.db.transaction import TransactionManagementError
from django.db.utils import DatabaseError, NotSupportedError
from django.utils.deprecation import RemovedInDjango30Warning
from django.utils.deprecation import (
RemovedInDjango30Warning, RemovedInDjango31Warning,
)
from django.utils.inspect import func_supports_parameter
FORCE = object()
@ -34,6 +36,7 @@ class SQLCompiler:
self.annotation_col_map = None
self.klass_info = None
self.ordering_parts = re.compile(r'(.*)\s(ASC|DESC)(.*)')
self._meta_ordering = None
def setup_query(self):
if all(self.query.alias_refcount[a] == 0 for a in self.query.alias_map):
@ -266,8 +269,13 @@ class SQLCompiler:
ordering = self.query.extra_order_by
elif not self.query.default_ordering:
ordering = self.query.order_by
elif self.query.order_by:
ordering = self.query.order_by
elif self.query.get_meta().ordering:
ordering = self.query.get_meta().ordering
self._meta_ordering = ordering
else:
ordering = (self.query.order_by or self.query.get_meta().ordering or [])
ordering = []
if self.query.standard_ordering:
asc, desc = ORDER_DIR['ASC']
else:
@ -536,7 +544,18 @@ class SQLCompiler:
raise NotImplementedError('annotate() + distinct(fields) is not implemented.')
order_by = order_by or self.connection.ops.force_no_ordering()
result.append('GROUP BY %s' % ', '.join(grouping))
if self._meta_ordering:
# When the deprecation ends, replace with:
# order_by = None
warnings.warn(
"%s QuerySet won't use Meta.ordering in Django 3.1. "
"Add .order_by('%s') to retain the current query." % (
self.query.model.__name__,
"', '".join(self._meta_ordering)
),
RemovedInDjango31Warning,
stacklevel=4,
)
if having:
result.append('HAVING %s' % having)
params.extend(h_params)

View File

@ -19,6 +19,8 @@ details on these changes.
* ``django.core.paginator.QuerySetPaginator`` will be removed.
* A model's ``Meta.ordering`` will no longer affect ``GROUP BY`` queries.
.. _deprecation-removed-in-3.0:
3.0

View File

@ -285,7 +285,8 @@ Django quotes column and table names behind the scenes.
ordering = [F('author').asc(nulls_last=True)]
Default ordering also affects :ref:`aggregation queries
<aggregation-ordering-interaction>`.
<aggregation-ordering-interaction>` but this won't be the case starting
in Django 3.1.
.. warning::

View File

@ -289,6 +289,15 @@ Miscellaneous
Features deprecated in 2.2
==========================
Model ``Meta.ordering`` will no longer affect ``GROUP BY`` queries
------------------------------------------------------------------
A model's ``Meta.ordering`` affecting ``GROUP BY`` queries (such as
``.annotate().values()``) is a common source of confusion. Such queries now
issue a deprecation warning with the advice to add an ``order_by()`` to retain
the current query. ``Meta.ordering`` will be ignored in such queries starting
in Django 3.1.
Miscellaneous
-------------

View File

@ -514,6 +514,13 @@ include the aggregate column.
Interaction with default ordering or ``order_by()``
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
.. deprecated:: 2.2
Starting in Django 3.1, the ordering from a model's ``Meta.ordering`` won't
be used in ``GROUP BY`` queries, such as ``.annotate().values()``. Since
Django 2.2, these queries issue a deprecation warning indicating to add an
explicit ``order_by()`` to the queryset to silence the warning.
Fields that are mentioned in the ``order_by()`` part of a queryset (or which
are used in the default ordering on a model) are used when selecting the
output data, even if they are not otherwise specified in the ``values()``

View File

@ -11,8 +11,11 @@ from django.db.models import (
Avg, Case, Count, DecimalField, F, IntegerField, Max, Q, StdDev, Sum,
Value, Variance, When,
)
from django.test import TestCase, skipUnlessAnyDBFeature, skipUnlessDBFeature
from django.test import (
TestCase, ignore_warnings, skipUnlessAnyDBFeature, skipUnlessDBFeature,
)
from django.test.utils import Approximate
from django.utils.deprecation import RemovedInDjango31Warning
from .models import (
Alfa, Author, Book, Bravo, Charlie, Clues, Entries, HardbackBook, ItemTag,
@ -106,6 +109,7 @@ class AggregationTests(TestCase):
for attr, value in kwargs.items():
self.assertEqual(getattr(obj, attr), value)
@ignore_warnings(category=RemovedInDjango31Warning)
def test_annotation_with_value(self):
values = Book.objects.filter(
name='Practical Django Projects',
@ -213,6 +217,7 @@ class AggregationTests(TestCase):
{'pages__sum': 3703}
)
@ignore_warnings(category=RemovedInDjango31Warning)
def test_annotation(self):
# Annotations get combined with extra select clauses
obj = Book.objects.annotate(mean_auth_age=Avg("authors__age")).extra(
@ -306,6 +311,7 @@ class AggregationTests(TestCase):
# If an annotation isn't included in the values, it can still be used
# in a filter
with ignore_warnings(category=RemovedInDjango31Warning):
qs = Book.objects.annotate(n_authors=Count('authors')).values('name').filter(n_authors__gt=2)
self.assertSequenceEqual(
qs, [
@ -450,6 +456,7 @@ class AggregationTests(TestCase):
with self.assertRaisesMessage(FieldError, msg):
Book.objects.all().annotate(num_authors=Count('authors__id')).aggregate(Max('foo'))
@ignore_warnings(category=RemovedInDjango31Warning)
def test_more(self):
# Old-style count aggregations can be mixed with new-style
self.assertEqual(
@ -679,7 +686,7 @@ class AggregationTests(TestCase):
)
# Regression for #10127 - Empty select_related() works with annotate
qs = Book.objects.filter(rating__lt=4.5).select_related().annotate(Avg('authors__age'))
qs = Book.objects.filter(rating__lt=4.5).select_related().annotate(Avg('authors__age')).order_by('name')
self.assertQuerysetEqual(
qs,
[
@ -803,6 +810,7 @@ class AggregationTests(TestCase):
with self.assertRaisesMessage(ValueError, msg):
Author.objects.annotate(book_contact_set=Avg('friends__age'))
@ignore_warnings(category=RemovedInDjango31Warning)
def test_pickle(self):
# Regression for #10197 -- Queries with aggregates can be pickled.
# First check that pickling is possible at all. No crash = success
@ -933,7 +941,9 @@ class AggregationTests(TestCase):
{'n_pages': 2078},
)
qs = HardbackBook.objects.annotate(n_authors=Count('book_ptr__authors')).values('name', 'n_authors')
qs = HardbackBook.objects.annotate(
n_authors=Count('book_ptr__authors'),
).values('name', 'n_authors').order_by('name')
self.assertSequenceEqual(
qs,
[
@ -945,7 +955,7 @@ class AggregationTests(TestCase):
],
)
qs = HardbackBook.objects.annotate(n_authors=Count('authors')).values('name', 'n_authors')
qs = HardbackBook.objects.annotate(n_authors=Count('authors')).values('name', 'n_authors').order_by('name')
self.assertSequenceEqual(
qs,
[
@ -1005,7 +1015,7 @@ class AggregationTests(TestCase):
def test_values_annotate_values(self):
qs = Book.objects.values("name").annotate(
n_authors=Count("authors")
).values_list("pk", flat=True)
).values_list("pk", flat=True).order_by('name')
self.assertEqual(list(qs), list(Book.objects.values_list("pk", flat=True)))
def test_having_group_by(self):
@ -1015,7 +1025,7 @@ class AggregationTests(TestCase):
n_authors=Count("authors")
).filter(
pages__gt=F("n_authors")
).values_list("name", flat=True)
).values_list("name", flat=True).order_by('name')
# Results should be the same, all Books have more pages than authors
self.assertEqual(
list(qs), list(Book.objects.values_list("name", flat=True))
@ -1035,7 +1045,7 @@ class AggregationTests(TestCase):
def test_annotation_disjunction(self):
qs = Book.objects.annotate(n_authors=Count("authors")).filter(
Q(n_authors=2) | Q(name="Python Web Development with Django")
)
).order_by('name')
self.assertQuerysetEqual(
qs, [
"Artificial Intelligence: A Modern Approach",
@ -1052,7 +1062,7 @@ class AggregationTests(TestCase):
Q(name="The Definitive Guide to Django: Web Development Done Right") |
(Q(name="Artificial Intelligence: A Modern Approach") & Q(n_authors=3))
)
)
).order_by('name')
self.assertQuerysetEqual(
qs,
[
@ -1200,6 +1210,7 @@ class AggregationTests(TestCase):
{'book__count__max': 2}
)
@ignore_warnings(category=RemovedInDjango31Warning)
def test_annotate_joins(self):
"""
The base table's join isn't promoted to LOUTER. This could
@ -1436,6 +1447,7 @@ class AggregationTests(TestCase):
query.filter(q1 | q2)
self.assertEqual(len(q2.children), 1)
@ignore_warnings(category=RemovedInDjango31Warning)
def test_fobj_group_by(self):
"""
An F() object referring to related column works correctly in group by.
@ -1513,6 +1525,7 @@ class JoinPromotionTests(TestCase):
qs = Charlie.objects.annotate(Count('alfa__name'))
self.assertIn(' LEFT OUTER JOIN ', str(qs.query))
@ignore_warnings(category=RemovedInDjango31Warning)
def test_non_nullable_fk_not_promoted(self):
qs = Book.objects.annotate(Count('contact__name'))
self.assertIn(' INNER JOIN ', str(qs.query))

View File

@ -1,9 +1,10 @@
from datetime import datetime
from operator import attrgetter
from django.db.models import DateTimeField, F, Max, OuterRef, Subquery
from django.db.models import Count, DateTimeField, F, Max, OuterRef, Subquery
from django.db.models.functions import Upper
from django.test import TestCase
from django.utils.deprecation import RemovedInDjango31Warning
from .models import Article, Author, OrderedByFArticle, Reference
@ -403,3 +404,11 @@ class OrderingTests(TestCase):
articles, ['Article 1', 'Article 4', 'Article 3', 'Article 2'],
attrgetter('headline')
)
def test_deprecated_values_annotate(self):
msg = (
"Article QuerySet won't use Meta.ordering in Django 3.1. Add "
".order_by('-pub_date', 'headline') to retain the current query."
)
with self.assertRaisesMessage(RemovedInDjango31Warning, msg):
list(Article.objects.values('author').annotate(Count('headline')))

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@ -2,8 +2,11 @@ import unittest
from django.db import NotSupportedError, connection, transaction
from django.db.models import Count
from django.test import TestCase, skipIfDBFeature, skipUnlessDBFeature
from django.test import (
TestCase, ignore_warnings, skipIfDBFeature, skipUnlessDBFeature,
)
from django.test.utils import CaptureQueriesContext
from django.utils.deprecation import RemovedInDjango31Warning
from .models import Tag
@ -11,6 +14,7 @@ from .models import Tag
@skipUnlessDBFeature('supports_explaining_query_execution')
class ExplainTests(TestCase):
@ignore_warnings(category=RemovedInDjango31Warning)
def test_basic(self):
querysets = [
Tag.objects.filter(name='test'),

View File

@ -1156,7 +1156,7 @@ class Queries1Tests(TestCase):
def test_ticket_20250(self):
# A negated Q along with an annotated queryset failed in Django 1.4
qs = Author.objects.annotate(Count('item'))
qs = qs.filter(~Q(extra__value=0))
qs = qs.filter(~Q(extra__value=0)).order_by('name')
self.assertIn('SELECT', str(qs.query))
self.assertQuerysetEqual(