参考 MySql中 delimiter 详解
其实就是告诉MySQL解释器，该段命令是否已经结束了，mysql是否可以执行了。默认情况下，delimiter是分号;
DELIMITER $$
DROP TRIGGER IF EXISTS `updateegopriceondelete`$$
CREATE TRIGGER `updateegopriceondelete` AFTER DELETE ON `customerinfo` FOR EACH ROW BEGIN
DELETE FROM egoprice WHERE customerId=OLD.customerId; END$$
DELIMITER ;