CREATE TABLE IF NOT EXISTS `t_test` ( `id` bigint(20) NOT NULL AUTO_INCREMENT COMMENT 'ID', `key` varchar(64) COLLATE utf8mb4_bin NOT NULL COMMENT 'value', PRIMARY KEY (`id`), KEY `unique_key` (`key`) ) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_bin; DROP TABLE `t_test` SELECT `id`, `key` FROM `t_test` WHERE `key` = #{key} INSERT INTO `t_test` (`id`, `key`) VALUE (0, #{key}) INSERT INTO `t_test` (`id`, `key`) VALUES (0, #{item}) DELETE FROM `t_test` WHERE `id` = #{id} SELECT SLEEP(#{time})