def reflects_json_type(self):
return only_on([
lambda config: against(config, "mysql >= 5.7") and not config.db.
dialect._is_mariadb,
"postgresql >= 9.3",
"sqlite >= 3.9",
])
def tuple_in(self):
def _sqlite_tuple_in(config):
return against(
config, "sqlite"
) and config.db.dialect.dbapi.sqlite_version_info >= (3, 15, 0)
return only_on(["mysql", "postgresql", _sqlite_tuple_in])
def update_from(self):
"""Target must support UPDATE..FROM syntax"""
return only_on(
["postgresql", "mssql", "mysql"],
"Backend does not support UPDATE..FROM",
)
def isolation_level(self):
return only_on(
("postgresql", "sqlite", "mysql", "mssql", "oracle"),
"DBAPI has no isolation level support",
) + fails_on(
"postgresql+pypostgresql",
"pypostgresql bombs on multiple isolation level calls",
)
def implicit_default_schema(self):
"""target system has a strong concept of 'default' schema that can
be referred to implicitly.
basically, PostgreSQL.
"""
return only_on(["postgresql"])
def json_type(self):
return only_on([
lambda config: against(config, "mysql") and (
(not config.db.dialect._is_mariadb and against(
config, "mysql >= 5.7")) or
(config.db.dialect._mariadb_normalized_version_info >=
(10, 2, 7))),
"postgresql >= 9.3",
self._sqlite_json,
])
def ctes_with_update_delete(self):
"""target database supports CTES that ride on top of a normal UPDATE
or DELETE statement which refers to the CTE in a correlated subquery.
"""
return only_on([
"postgresql",
"mssql",
# "oracle" - oracle can do this but SQLAlchemy doesn't support
# their syntax yet
])
def ctes(self):
"""Target database supports CTEs"""
return only_on([
lambda config: against(config, "mysql") and (
(config.db.dialect._is_mariadb and config.db.dialect.
_mariadb_normalized_version_info >=
(10, 2)) or (not config.db.dialect._is_mariadb and config.db.
dialect.server_version_info >= (8, ))),
"postgresql",
"mssql",
"oracle",
"sqlite>=3.8.3",
])
def delete_from(self):
"""Target must support DELETE FROM..FROM or DELETE..USING syntax"""
return only_on(
["postgresql", "mssql", "mysql", "sybase"],
"Backend does not support DELETE..FROM",
)
def array_type(self):
return only_on([
lambda config: against(config, "postgresql") and not against(
config, "+pg8000") and not against(config, "+zxjdbc")
])
def temporary_views(self):
"""target database supports temporary views"""
return only_on(["sqlite", "postgresql"]) + skip_if(
self._sqlite_file_db)
def indexes_with_expressions(self):
return only_on(["postgresql", "sqlite>=3.9.0"])
def temp_table_names(self):
"""target dialect supports listing of temporary table names"""
return only_on(["sqlite", "oracle"]) + skip_if(self._sqlite_file_db)
def cross_schema_fk_reflection(self):
"""target system must support reflection of inter-schema foreign
keys"""
return only_on(["postgresql", "mysql", "mssql"])
def postgresql_jsonb(self):
return only_on("postgresql >= 9.4") + skip_if(
lambda config: config.db.dialect.driver == "pg8000" and config.db.
dialect._dbapi_version <= (1, 10, 1))
def psycopg2_compatibility(self):
return only_on(["postgresql+psycopg2", "postgresql+psycopg2cffi"])
def foreign_key_constraint_option_reflection_onupdate(self):
return only_on(["postgresql", "mysql", "sqlite"])
def sequences_as_server_defaults(self):
"""Target database must support SEQUENCE as a server side default."""
return only_on("postgresql",
"doesn't support sequences as a server side default.")
def psycopg2_or_pg8000_compatibility(self):
return only_on([
"postgresql+psycopg2",
"postgresql+psycopg2cffi",
"postgresql+pg8000",
])
def comment_reflection(self):
return only_on(["postgresql", "mysql", "oracle"])
def python_profiling_backend(self):
return only_on([self._sqlite_memory_db])
def mssql_freetds(self):
return only_on(["mssql+pymssql"])
def timestamp_microseconds(self):
"""target dialect supports representation of Python
datetime.datetime() with microsecond objects but only
if TIMESTAMP is used."""
return only_on(["oracle"])
def deferrable_fks(self):
"""target database must support deferrable fks"""
return only_on(["oracle"])
