import operator
from django.db import transaction
from django.db.backends.base.features import BaseDatabaseFeatures
from django.db.utils import OperationalError
from django.utils.functional import cached_property
from .base import Database
class DatabaseFeatures(BaseDatabaseFeatures):
minimum_database_version = (3, 31)
test_db_allows_multiple_connections = False
supports_unspecified_pk = True
supports_timezones = False
max_query_params = 999
supports_transactions = True
atomic_transactions = False
can_rollback_ddl = True
can_create_inline_fk = False
requires_literal_defaults = True
can_clone_databases = True
supports_temporal_subtraction = True
ignores_table_name_case = True
supports_cast_with_precision = False
time_cast_precision = 3
can_release_savepoints = True
has_case_insensitive_like = True
# Is "ALTER TABLE ... DROP COLUMN" supported?
can_alter_table_drop_column = Database.sqlite_version_info >= (3, 35, 5)
supports_parentheses_in_compound = False
can_defer_constraint_checks = True
supports_over_clause = True
supports_frame_range_fixed_distance = True
supports_frame_exclusion = True
supports_aggregate_filter_clause = True
order_by_nulls_first = True
supports_json_field_contains = False
supports_update_conflicts = True
supports_update_conflicts_with_target = True
supports_stored_generated_columns = True
supports_virtual_generated_columns = True
test_collations = {
"ci": "nocase",
"cs": "binary",
"non_default": "nocase",
"virtual": "nocase",
}
django_test_expected_failures = {
# The django_format_dtdelta() function doesn't properly handle mixed
# Date/DateTime fields and timedeltas.
"expressions.tests.FTimeDeltaTests.test_mixed_comparisons1",
}
create_test_table_with_composite_primary_key = """
CREATE TABLE test_table_composite_pk (
column_1 INTEGER NOT NULL,
column_2 INTEGER NOT NULL,
PRIMARY KEY(column_1, column_2)
)
"""
insert_test_table_with_defaults = 'INSERT INTO {} ("null") VALUES (1)'
supports_default_keyword_in_insert = False
@cached_property
def django_test_skips(self):
skips = {
"SQLite stores values rounded to 15 significant digits.": {
"model_fields.test_decimalfield.DecimalFieldTests."
"test_fetch_from_db_without_float_rounding",
},
"SQLite naively remakes the table on field alteration.": {
"schema.tests.SchemaTests.test_unique_no_unnecessary_fk_drops",
"schema.tests.SchemaTests.test_unique_and_reverse_m2m",
"schema.tests.SchemaTests."
"test_alter_field_default_doesnt_perform_queries",
"schema.tests.SchemaTests."
"test_rename_column_renames_deferred_sql_references",
},
"SQLite doesn't support negative precision for ROUND().": {
"db_functions.math.test_round.RoundTests."
"test_null_with_negative_precision",
"db_functions.math.test_round.RoundTests."
"test_decimal_with_negative_precision",
"db_functions.math.test_round.RoundTests."
"test_float_with_negative_precision",
"db_functions.math.test_round.RoundTests."
"test_integer_with_negative_precision",
},
"The actual query cannot be determined on SQLite": {
"backends.base.test_base.ExecuteWrapperTests.test_wrapper_debug",
},
}
if self.connection.is_in_memory_db():
skips.update(
{
"the sqlite backend's close() method is a no-op when using an "
"in-memory database": {
"servers.test_liveserverthread.LiveServerThreadTest."
"test_closes_connections",
"servers.tests.LiveServerTestCloseConnectionTest."
"test_closes_connections",
},
"For SQLite in-memory tests, closing the connection destroys"
"the database.": {
"test_utils.tests.AssertNumQueriesUponConnectionTests."
"test_ignores_connection_configuration_queries",
},
}
)
else:
skips.update(
{
"Only connections to in-memory SQLite databases are passed to the "
"server thread.": {
"servers.tests.LiveServerInMemoryDatabaseLockTest."
"test_in_memory_database_lock",
},
"multiprocessing's start method is checked only for in-memory "
"SQLite databases": {
"backends.sqlite.test_creation.TestDbSignatureTests."
"test_get_test_db_clone_settings_not_supported",
},
}
)
return skips
@cached_property
def introspected_field_types(self):
return {
**super().introspected_field_types,
"BigAutoField": "AutoField",
"DurationField": "BigIntegerField",
"GenericIPAddressField": "CharField",
"SmallAutoField": "AutoField",
}
@cached_property
def supports_json_field(self):
with self.connection.cursor() as cursor:
try:
with transaction.atomic(self.connection.alias):
cursor.execute('SELECT JSON(\'{"a": "b"}\')')
except OperationalError:
return False
return True
can_introspect_json_field = property(operator.attrgetter("supports_json_field"))
has_json_object_function = property(operator.attrgetter("supports_json_field"))
@cached_property
def can_return_columns_from_insert(self):
return Database.sqlite_version_info >= (3, 35)
can_return_rows_from_bulk_insert = property(
operator.attrgetter("can_return_columns_from_insert")
)