CREATE TABLE `sys_user` (
  `id` bigint(20) NOT NULL COMMENT '主鍵ID',
  `name` varchar(30) DEFAULT NULL COMMENT '姓名',
  `age` int(11) DEFAULT NULL COMMENT '年齡',
  `email` varchar(50) DEFAULT NULL COMMENT '郵箱',
  `deleted` tinyint(1) DEFAULT NULL COMMENT '是否刪除',
  `create_time` datetime DEFAULT NULL COMMENT '創(chuàng)建時間',
  `create_id` bigint(20) DEFAULT NULL COMMENT '創(chuàng)建人',
  `update_id` bigint(20) DEFAULT NULL COMMENT '操作人',
  `update_time` datetime DEFAULT NULL COMMENT '更新時間',
  `status` varchar(255) DEFAULT NULL COMMENT '狀態(tài)',
  `dog` text DEFAULT NULL COMMENT '狗',
  `version` int(11) DEFAULT NULL COMMENT '版本號',
  PRIMARY KEY (`id`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8;
INSERT INTO `sys_user`(`id`, `name`, `age`, `email`, `deleted`, `create_time`, `create_id`, `update_id`, `update_time`, `status`, `dog`, `version`) VALUES (1, 'gukong', 19, 'test1@baomidou.com', 0, NULL, NULL, NULL, NULL, NULL, NULL, 0);

--開啟事務
BEGIN
--對行加鎖
SELECT * FROM `sys_user` where id = 1 for UPDATE
--修改加鎖行的數(shù)據(jù)
update sys_user set name = 'gukong',age = 18 where id = 1;
--提交事務
commit;

--開啟事務
BEGIN
--對行加鎖
SELECT * FROM `sys_user` where id = 1 for UPDATE
--修改加鎖行的數(shù)據(jù)
update sys_user set name = 'kulilin',age = 20 where id = 1;
--提交事務
commit;
update sys_user set name = 'kulilin',age = 20 where id = 1;

-- version = 0
SELECT * FROM `sys_user` where id = 1 
update sys_user set name='小明',version = version+1 and age = 20 where id = 1 and version = 0;
-- version = 0 ，而此時version=1,更新失敗
SELECT * FROM `sys_user` where id = 1 
update sys_user set name = '小紅' version = version+1 and age = 25 where id = 1 and version = 0;