def scheme(self):
        return self.input.scheme()
target platform supports INSERT with no values, i.e.
dataset/ETHPy150Open uwescience/raco/raco/algebra.py/UnaryOperator.scheme--crossover with--dataset/ETHPy150Open RoseOu/flasky/venv/lib/python2.7/site-packages/sqlalchemy/testing/requirements.py/SuiteRequirements.empty_inserts