django/tests/queries/test_qs_combinators.py

109 lines
4.6 KiB
Python

from django.db.models import F, IntegerField, Value
from django.db.utils import DatabaseError
from django.test import TestCase, skipIfDBFeature, skipUnlessDBFeature
from .models import Number, ReservedName
@skipUnlessDBFeature('supports_select_union')
class QuerySetSetOperationTests(TestCase):
@classmethod
def setUpTestData(cls):
Number.objects.bulk_create(Number(num=i) for i in range(10))
def number_transform(self, value):
return value.num
def assertNumbersEqual(self, queryset, expected_numbers, ordered=True):
self.assertQuerysetEqual(queryset, expected_numbers, self.number_transform, ordered)
def test_simple_union(self):
qs1 = Number.objects.filter(num__lte=1)
qs2 = Number.objects.filter(num__gte=8)
qs3 = Number.objects.filter(num=5)
self.assertNumbersEqual(qs1.union(qs2, qs3), [0, 1, 5, 8, 9], ordered=False)
@skipUnlessDBFeature('supports_select_intersection')
def test_simple_intersection(self):
qs1 = Number.objects.filter(num__lte=5)
qs2 = Number.objects.filter(num__gte=5)
qs3 = Number.objects.filter(num__gte=4, num__lte=6)
self.assertNumbersEqual(qs1.intersection(qs2, qs3), [5], ordered=False)
@skipUnlessDBFeature('supports_select_difference')
def test_simple_difference(self):
qs1 = Number.objects.filter(num__lte=5)
qs2 = Number.objects.filter(num__lte=4)
self.assertNumbersEqual(qs1.difference(qs2), [5], ordered=False)
def test_union_distinct(self):
qs1 = Number.objects.all()
qs2 = Number.objects.all()
self.assertEqual(len(list(qs1.union(qs2, all=True))), 20)
self.assertEqual(len(list(qs1.union(qs2))), 10)
def test_union_bad_kwarg(self):
qs1 = Number.objects.all()
msg = "union() received an unexpected keyword argument 'bad'"
with self.assertRaisesMessage(TypeError, msg):
self.assertEqual(len(list(qs1.union(qs1, bad=True))), 20)
def test_limits(self):
qs1 = Number.objects.all()
qs2 = Number.objects.all()
self.assertEqual(len(list(qs1.union(qs2)[:2])), 2)
def test_ordering(self):
qs1 = Number.objects.filter(num__lte=1)
qs2 = Number.objects.filter(num__gte=2, num__lte=3)
self.assertNumbersEqual(qs1.union(qs2).order_by('-num'), [3, 2, 1, 0])
@skipUnlessDBFeature('supports_slicing_ordering_in_compound')
def test_ordering_subqueries(self):
qs1 = Number.objects.order_by('num')[:2]
qs2 = Number.objects.order_by('-num')[:2]
self.assertNumbersEqual(qs1.union(qs2).order_by('-num')[:4], [9, 8, 1, 0])
@skipIfDBFeature('supports_slicing_ordering_in_compound')
def test_unsupported_ordering_slicing_raises_db_error(self):
qs1 = Number.objects.all()
qs2 = Number.objects.all()
msg = 'LIMIT/OFFSET not allowed in subqueries of compound statements'
with self.assertRaisesMessage(DatabaseError, msg):
list(qs1.union(qs2[:10]))
msg = 'ORDER BY not allowed in subqueries of compound statements'
with self.assertRaisesMessage(DatabaseError, msg):
list(qs1.order_by('id').union(qs2))
@skipIfDBFeature('supports_select_intersection')
def test_unsupported_intersection_raises_db_error(self):
qs1 = Number.objects.all()
qs2 = Number.objects.all()
msg = 'intersection not supported on this database backend'
with self.assertRaisesMessage(DatabaseError, msg):
list(qs1.intersection(qs2))
def test_combining_multiple_models(self):
ReservedName.objects.create(name='99 little bugs', order=99)
qs1 = Number.objects.filter(num=1).values_list('num', flat=True)
qs2 = ReservedName.objects.values_list('order')
self.assertEqual(list(qs1.union(qs2).order_by('num')), [1, 99])
def test_order_raises_on_non_selected_column(self):
qs1 = Number.objects.filter().annotate(
annotation=Value(1, IntegerField()),
).values('annotation', num2=F('num'))
qs2 = Number.objects.filter().values('id', 'num')
# Should not raise
list(qs1.union(qs2).order_by('annotation'))
list(qs1.union(qs2).order_by('num2'))
msg = 'ORDER BY term does not match any column in the result set'
# 'id' is not part of the select
with self.assertRaisesMessage(DatabaseError, msg):
list(qs1.union(qs2).order_by('id'))
# 'num' got realiased to num2
with self.assertRaisesMessage(DatabaseError, msg):
list(qs1.union(qs2).order_by('num'))
# switched order, now 'exists' again:
list(qs2.union(qs1).order_by('num'))