mysql delete duplicate field data the way

1, create a table

CREATE TABLE `user` (
  `id` int(11) DEFAULT NULL,
  `name` varchar(255) DEFAULT NULL,
  `age` int(11) DEFAULT NULL,
  `address` varchar(255) DEFAULT NULL
) ENGINE=InnoDB DEFAULT CHARSET=utf8;

2, the data inserted into the corresponding

INSERT INTO `user` VALUES ('1', 'zhangsan', '20', '上海');
INSERT INTO `user` VALUES ('2', 'zhangsan', '20', '北京');
INSERT INTO `user` VALUES ('3', 'lisi', '25', '北京');
INSERT INTO `user` VALUES ('4', 'lisi', '25', '深圳');
INSERT INTO `user` VALUES ('5', 'wangwu', '30', ' Shenzhen ' );
 INSERT  INTO ` the User ` VALUES ( ' 6 ' , ' wangwu ' , ' 30 ' , ' Shanghai ' );
 INSERT  INTO ` the User ` VALUES ( ' 7 ' , ' zhaoliu ' , ' 35 ' , ' Guangzhou ' );

3, common operations

# Copy a table
 the CREATE  TABLE ` the User ` AS  the SELECT  *  the FROM `user_temp` 
# create an empty table 
the CREATE  TABLE user_temp1 like ` the User ` 
# delete a table 
DROP  TABLE ` the User `

4, aid count keyword

DELETE FROM `user` WHERE id in(
    SELECT v.minid FROM(
            SELECT COUNT(*) num,`name`,age,MAX(id) minid FROM `user` GROUP BY `name`,age 
    ) v WHERE v.num>1
)

5, the use of having keywords

DELETE FROM `user` WHERE id in(
    SELECT id FROM(
        SELECT MAX(id) id,`name`,age,address FROM `user` t GROUP BY t.`name` HAVING COUNT(`name`)>1
    ) v
)

Note: delete statement delete a query result set is not going to work, have to rely on word query is embedded view to complete the deletion function