MySQL database security A way to prevent corruption
- 2020-06-19 11:55:17
- OfStack
The MySQL database can be triggered so that it cannot modify the data of some fields without affecting the modification of others.
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;
Here's another example:
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;
Add 1 new piece of data for each data change
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);
Protect the user's balance from being modified
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;