from django.db.models import F, IntegerField, Value from django.db.utils import DatabaseError, NotSupportedError 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) @skipUnlessDBFeature('supports_select_intersection') def test_intersection_with_empty_qs(self): qs1 = Number.objects.all() qs2 = Number.objects.none() qs3 = Number.objects.filter(pk__in=[]) self.assertEqual(len(qs1.intersection(qs2)), 0) self.assertEqual(len(qs1.intersection(qs3)), 0) self.assertEqual(len(qs2.intersection(qs1)), 0) self.assertEqual(len(qs3.intersection(qs1)), 0) self.assertEqual(len(qs2.intersection(qs2)), 0) self.assertEqual(len(qs3.intersection(qs3)), 0) @skipUnlessDBFeature('supports_select_difference') def test_difference_with_empty_qs(self): qs1 = Number.objects.all() qs2 = Number.objects.none() qs3 = Number.objects.filter(pk__in=[]) self.assertEqual(len(qs1.difference(qs2)), 10) self.assertEqual(len(qs1.difference(qs3)), 10) self.assertEqual(len(qs2.difference(qs1)), 0) self.assertEqual(len(qs3.difference(qs1)), 0) self.assertEqual(len(qs2.difference(qs2)), 0) self.assertEqual(len(qs3.difference(qs3)), 0) def test_union_with_empty_qs(self): qs1 = Number.objects.all() qs2 = Number.objects.none() qs3 = Number.objects.filter(pk__in=[]) self.assertEqual(len(qs1.union(qs2)), 10) self.assertEqual(len(qs2.union(qs1)), 10) self.assertEqual(len(qs1.union(qs3)), 10) self.assertEqual(len(qs3.union(qs1)), 10) self.assertEqual(len(qs2.union(qs1, qs1, qs1)), 10) self.assertEqual(len(qs2.union(qs1, qs1, all=True)), 20) self.assertEqual(len(qs2.union(qs2)), 0) self.assertEqual(len(qs3.union(qs3)), 0) 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]) def test_count_union(self): qs1 = Number.objects.filter(num__lte=1).values('num') qs2 = Number.objects.filter(num__gte=2, num__lte=3).values('num') self.assertEqual(qs1.union(qs2).count(), 4) def test_count_union_empty_result(self): qs = Number.objects.filter(pk__in=[]) self.assertEqual(qs.union(qs).count(), 0) @skipUnlessDBFeature('supports_select_difference') def test_count_difference(self): qs1 = Number.objects.filter(num__lt=10) qs2 = Number.objects.filter(num__lt=9) self.assertEqual(qs1.difference(qs2).count(), 1) @skipUnlessDBFeature('supports_select_intersection') def test_count_intersection(self): qs1 = Number.objects.filter(num__gte=5) qs2 = Number.objects.filter(num__lte=5) self.assertEqual(qs1.intersection(qs2).count(), 1) @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 is not supported on this database backend' with self.assertRaisesMessage(NotSupportedError, 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'))