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MYSQL ɾ³ýͬһ±íÖÐÖظ´¼Ç¼
CREATE TABLE `user` (
`db_id` varchar(255) NOT NULL,
`name` varchar(45) default NULL,
`age` int(10) unsigned NOT NULL,
`address` varchar(45) default NULL,
PRIMARY KEY (`db_id`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8;
// ±£ÁôÏàͬageÖÐname±È½Ï×î´óµÄ¼Ç¼
delete users as a from users as a,
(
select age,max(name) as mName from users group by age
) as b
where a.age = b.age and a.name <> b.mName;
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