MySQL数据库可以通过触发器，使之无法修改某些字段的数据，同时又不会影响修改其他字段。
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;
