mysql 索引

drop index name on table_test ;

创建表时直接设置:

DROP TABLE IF EXISTS `student`;
CREATE TABLE `student` (
  `stu_id` int(11) NOT NULL AUTO_INCREMENT,
  `name` varchar(255) DEFAULT NULL,
  PRIMARY KEY (`stu_id`),
  UNIQUE KEY `UK_student_name` (`name`) 
) ENGINE=InnoDB AUTO_INCREMENT=12 DEFAULT CHARSET=utf8;

ALTER TABLE t_repay_portion DROP index account_no_loan_code_period;
alter table t_repay_portion add unique index account_no_loan_code_frozen_order_id_period(account_no,loan_code,frozen_order_id,period);

创建唯一索引:

create unique index UK_student_name on student (name);

建表后添加约束:

alter table student add constraint uk_student_name unique (name);