mirror of
https://github.com/django/django.git
synced 2024-12-27 11:35:53 +00:00
4a103086d5
Thanks Vinay Sajip for the support of his django3 branch and Jannis Leidel for the review.
119 lines
5.0 KiB
Python
119 lines
5.0 KiB
Python
from __future__ import absolute_import
|
|
|
|
from django.db.models import Max
|
|
from django.test import TestCase, skipUnlessDBFeature
|
|
from django.test.utils import str_prefix
|
|
|
|
from .models import Tag, Celebrity, Fan, Staff, StaffTag
|
|
|
|
class DistinctOnTests(TestCase):
|
|
def setUp(self):
|
|
t1 = Tag.objects.create(name='t1')
|
|
t2 = Tag.objects.create(name='t2', parent=t1)
|
|
t3 = Tag.objects.create(name='t3', parent=t1)
|
|
t4 = Tag.objects.create(name='t4', parent=t3)
|
|
t5 = Tag.objects.create(name='t5', parent=t3)
|
|
|
|
p1_o1 = Staff.objects.create(id=1, name="p1", organisation="o1")
|
|
p2_o1 = Staff.objects.create(id=2, name="p2", organisation="o1")
|
|
p3_o1 = Staff.objects.create(id=3, name="p3", organisation="o1")
|
|
p1_o2 = Staff.objects.create(id=4, name="p1", organisation="o2")
|
|
p1_o1.coworkers.add(p2_o1, p3_o1)
|
|
StaffTag.objects.create(staff=p1_o1, tag=t1)
|
|
StaffTag.objects.create(staff=p1_o1, tag=t1)
|
|
|
|
celeb1 = Celebrity.objects.create(name="c1")
|
|
celeb2 = Celebrity.objects.create(name="c2")
|
|
|
|
self.fan1 = Fan.objects.create(fan_of=celeb1)
|
|
self.fan2 = Fan.objects.create(fan_of=celeb1)
|
|
self.fan3 = Fan.objects.create(fan_of=celeb2)
|
|
|
|
@skipUnlessDBFeature('can_distinct_on_fields')
|
|
def test_basic_distinct_on(self):
|
|
"""QuerySet.distinct('field', ...) works"""
|
|
# (qset, expected) tuples
|
|
qsets = (
|
|
(
|
|
Staff.objects.distinct().order_by('name'),
|
|
['<Staff: p1>', '<Staff: p1>', '<Staff: p2>', '<Staff: p3>'],
|
|
),
|
|
(
|
|
Staff.objects.distinct('name').order_by('name'),
|
|
['<Staff: p1>', '<Staff: p2>', '<Staff: p3>'],
|
|
),
|
|
(
|
|
Staff.objects.distinct('organisation').order_by('organisation', 'name'),
|
|
['<Staff: p1>', '<Staff: p1>'],
|
|
),
|
|
(
|
|
Staff.objects.distinct('name', 'organisation').order_by('name', 'organisation'),
|
|
['<Staff: p1>', '<Staff: p1>', '<Staff: p2>', '<Staff: p3>'],
|
|
),
|
|
(
|
|
Celebrity.objects.filter(fan__in=[self.fan1, self.fan2, self.fan3]).\
|
|
distinct('name').order_by('name'),
|
|
['<Celebrity: c1>', '<Celebrity: c2>'],
|
|
),
|
|
# Does combining querysets work?
|
|
(
|
|
(Celebrity.objects.filter(fan__in=[self.fan1, self.fan2]).\
|
|
distinct('name').order_by('name')
|
|
|Celebrity.objects.filter(fan__in=[self.fan3]).\
|
|
distinct('name').order_by('name')),
|
|
['<Celebrity: c1>', '<Celebrity: c2>'],
|
|
),
|
|
(
|
|
StaffTag.objects.distinct('staff','tag'),
|
|
['<StaffTag: t1 -> p1>'],
|
|
),
|
|
(
|
|
Tag.objects.order_by('parent__pk', 'pk').distinct('parent'),
|
|
['<Tag: t2>', '<Tag: t4>', '<Tag: t1>'],
|
|
),
|
|
(
|
|
StaffTag.objects.select_related('staff').distinct('staff__name').order_by('staff__name'),
|
|
['<StaffTag: t1 -> p1>'],
|
|
),
|
|
# Fetch the alphabetically first coworker for each worker
|
|
(
|
|
(Staff.objects.distinct('id').order_by('id', 'coworkers__name').
|
|
values_list('id', 'coworkers__name')),
|
|
[str_prefix("(1, %(_)s'p2')"), str_prefix("(2, %(_)s'p1')"),
|
|
str_prefix("(3, %(_)s'p1')"), "(4, None)"]
|
|
),
|
|
)
|
|
for qset, expected in qsets:
|
|
self.assertQuerysetEqual(qset, expected)
|
|
self.assertEqual(qset.count(), len(expected))
|
|
|
|
# Combining queries with different distinct_fields is not allowed.
|
|
base_qs = Celebrity.objects.all()
|
|
self.assertRaisesMessage(
|
|
AssertionError,
|
|
"Cannot combine queries with different distinct fields.",
|
|
lambda: (base_qs.distinct('id') & base_qs.distinct('name'))
|
|
)
|
|
|
|
# Test join unreffing
|
|
c1 = Celebrity.objects.distinct('greatest_fan__id', 'greatest_fan__fan_of')
|
|
self.assertIn('OUTER JOIN', str(c1.query))
|
|
c2 = c1.distinct('pk')
|
|
self.assertNotIn('OUTER JOIN', str(c2.query))
|
|
|
|
@skipUnlessDBFeature('can_distinct_on_fields')
|
|
def test_distinct_not_implemented_checks(self):
|
|
# distinct + annotate not allowed
|
|
with self.assertRaises(NotImplementedError):
|
|
Celebrity.objects.annotate(Max('id')).distinct('id')[0]
|
|
with self.assertRaises(NotImplementedError):
|
|
Celebrity.objects.distinct('id').annotate(Max('id'))[0]
|
|
|
|
# However this check is done only when the query executes, so you
|
|
# can use distinct() to remove the fields before execution.
|
|
Celebrity.objects.distinct('id').annotate(Max('id')).distinct()[0]
|
|
# distinct + aggregate not allowed
|
|
with self.assertRaises(NotImplementedError):
|
|
Celebrity.objects.distinct('id').aggregate(Max('id'))
|
|
|