def get_foreign_key_referential_action_sql(self, action):
        """
        Returns the given referential action in uppercase if valid, otherwise throws an exception.

        :param action: The action
        :type action: str

        :rtype: str
        """
        action = action.upper()
        if action not in ['CASCADE', 'SET NULL', 'NO ACTION', 'RESTRICT', 'SET DEFAULT']:
            raise DBALException('Invalid foreign key action: %s' % action)

        return action
dataset/ETHPy150Open sdispater/orator/orator/dbal/platforms/platform.py/Platform.get_foreign_key_referential_action_sql/original