1.建立表脚本

CREATE DATABASE `spring`  DEFAULT CHARACTER SET utf8;USE `spring`;CREATE TABLE `account` (  `id` int(10) unsigned NOT NULL AUTO_INCREMENT,  `username` varchar(45) NOT NULL,  `password` varchar(45) NOT NULL,  `birthday` datetime NOT NULL,  `email` varchar(45) NOT NULL,  PRIMARY KEY (`id`)) ENGINE=InnoDB AUTO_INCREMENT=8 DEFAULT CHARSET=utf8;CREATE TABLE `account_flow` (  `id` int(11) DEFAULT NULL,  `username` varchar(45) DEFAULT NULL,  `add_time` datetime DEFAULT CURRENT_TIMESTAMP,  `flag` int(11) DEFAULT '0') ENGINE=InnoDB DEFAULT CHARSET=utf8;

 2.建立触发器

DELIMITER $$CREATE TRIGGER `account_insert_trigger` AFTER INSERT ON `account` FOR EACH ROW BEGIN	INSERT INTO account_flow (id,username,flag) 		VALUES (new.id, new.username, 1);    END DELIMITER ; DELIMITER $$CREATE TRIGGER `account_update_trigger` AFTER UPDATE ON `account` FOR EACH ROW BEGIN	if old.username != new.username then		INSERT INTO account_flow (id,username,flag) 		VALUES (new.id, new.username, 2);	end if;    ENDDELIMITER ;

 3.触发器说明 （注意new,old关键字）

account_insert_trigger： 添加account记录的时候，同时添加一条记录到account_flow表中。

account_update_trigger：修改account记录的时候，判断username是否修改，如果修改同时在account_flow表中添加一条记录。