一、查询双重的记录：
SELECT username FROM info where sex='1' GROUP BY 'username' HAVING count(*)>1;
二、Mysql添加权限
GRANT select,LOCK TABLES on database.* to user@localhost identified by '123456fdgdf#df';
三、Mysql追加权限
GRANT SELECT,INSERT,UPDATE,DELETE,INDEX ON database.* TO user@localhost;
四、Mysql删除权限
SELECT username FROM info where sex='1' GROUP BY 'username' HAVING count(*)>1;
二、Mysql添加权限
GRANT select,LOCK TABLES on database.* to user@localhost identified by '123456fdgdf#df';
三、Mysql追加权限
GRANT SELECT,INSERT,UPDATE,DELETE,INDEX ON database.* TO user@localhost;
四、Mysql删除权限
