* 建表語句

CREATE TABLE `config` (
  `id` int(11) NOT NULL AUTO_INCREMENT,
  `name` varchar(255) NOT NULL COMMENT '配置項',
  `value` varchar(255) NOT NULL COMMENT '配置值',
  PRIMARY KEY (`id`),
  UNIQUE KEY `uniq_config_name` (`name`)
) ENGINE=InnoDB AUTO_INCREMENT=1 DEFAULT CHARSET=utf8;

* 新增索引

alter table `config` add index idx_config_name(`name`);

* 刪除索引 alter table `config` drop index idx_config_name;