def cpython(fn):
return _chain_decorators_on(
fn,
only_if(lambda: util.cpython,
"cPython interpreter needed"
)
)
def window_functions(fn):
return only_if([
"postgresql", "mssql", "oracle"
], "Backend does not support window functions")(fn)
def returning(fn):
return only_if(["postgresql", "mssql", "oracle", "firebird"],
"'returning' not supported by database"
)(fn)
def sequences(fn):
"""Target database must support SEQUENCEs."""
return only_if([
"postgresql", "firebird", "oracle"
], "no SEQUENCE support")(fn)