以下节选择《Netkiller Architect 手札》地址 http://www.netkiller.cn/architect/
接下来几周的话题是数据库安全。
通过触发器,使之无法修改某些字段的数据,同时不影响修改其他字段。
DROP TRIGGER IF EXISTS `members`;
SET @OLD_SQL_MODE=@@SQL_MODE, SQL_MODE='';
DELIMITER //
CREATE TRIGGER `members` BEFORE UPDATE ON `members` FOR EACH ROW BEGIN
set new.name = old.name;
set new.cellphone = old.cellphone;
set new.email = old.email;
set new.password = old.password;
END//
DELIMITER ;
SET SQL_MODE=@OLD_SQL_MODE;
再举一个例子
CREATE TABLE `account` (
`id` INT(10) UNSIGNED NOT NULL AUTO_INCREMENT,
`user` VARCHAR(50) NOT NULL DEFAULT '0',
`cash` FLOAT NOT NULL DEFAULT '0',
PRIMARY KEY (`id`)
)
COLLATE='utf8_general_ci'
ENGINE=InnoDB;
每一次数据变化新增一条数据
INSERT INTO `test`.`account` (`user`, `cash`) VALUES ('neo', -10);
INSERT INTO `test`.`account` (`user`, `cash`) VALUES ('neo', -5);
INSERT INTO `test`.`account` (`user`, `cash`) VALUES ('neo', 30);
INSERT INTO `test`.`account` (`user`, `cash`) VALUES ('neo', -20);
保护用户的余额不被修改
DROP TRIGGER IF EXISTS `account`;
SET @OLD_SQL_MODE=@@SQL_MODE, SQL_MODE='';
DELIMITER //
CREATE TRIGGER `account` BEFORE UPDATE ON `account` FOR EACH ROW BEGIN
set new.cash = old.cash;
END//
DELIMITER ;
SET SQL_MODE=@OLD_SQL_MODE;