text: CREATE TABLE `missions` (
    `id` int(11) unsigned NOT NULL AUTO_INCREMENT,
    `state` enum('need_sent','ready_to_charge','charging','charging_complete') NOT NULL DEFAULT 'need_sent',
    `need_created_at` datetime DEFAULT NULL,
    `charging_started_at` datetime DEFAULT NULL,
    `charging_completed_at` datetime DEFAULT NULL,
    PRIMARY KEY (`id`)
  ) ENGINE=InnoDB AUTO_INCREMENT=1 DEFAULT CHARSET=utf8;