1....准备工作
创建测试表:
CREATE TABLE `t4` (
`id` int unsigned NOT NULL AUTO_INCREMENT,
`i1` int DEFAULT '0',...`i2` int DEFAULT '0',
PRIMARY KEY (`id`) USING BTREE,
UNIQUE KEY `uniq_i1` (`i1`)
) ENGINE=InnoDB...DEFAULT CHARSET=utf8mb3;
插入测试数据:
INSERT INTO `t4` (`id`, `i1`, `i2`) VALUES
(1, 11, 21), (2, 12, 22...i2) values (2, 120, 220)
on duplicate key update i1 = values(i1), i2 = values(i2);
查看加锁情况:
select