事务

CREATE DATABASE shop CHARACTER SET utf8 COLLATE utf8_general_ci
USE shop

CREATE TABLE `account`(
`id` INT(3) NOT NULL AUTO_INCREMENT,
`name` VARCHAR(30) NOT NULL,
`monet` DECIMAL(9,2) NOT NULL,
PRIMARY KEY(`id`)
) ENGINE=INNODB DEFAULT CHARSET=utf8;

INSERT INTO `account`(`name`,`money`)
VALUES ('a',2000.00),('b',3000.00)

-- 模拟转账：事务
SET autocommit = 0; -- 关闭自动提交事务
START TRANSACTION -- 开启一个事务
UPDATE account SET money=money-500 WHERE `name` = 'a'; -- a减500
UPDATE account SET money=money+500 WHERE `name` = 'b'; -- b加500

COMMIT; -- 提交事务,一提交就被持久化
ROLLBACK; -- 回滚
SET autocommit = 1; -- 回复默认值