今天在坛子上看到了，顺便写下来。

有两种方法：

1、效率不高，因为有子查询。但是简洁。而且我对SOCRES表做了INDEX。所以性能上也差不了多少。

mysql> show create table scores\G *************************** 1. row ***************************        Table: scores Create Table: CREATE TABLE `scores` (   `id` int(11) NOT NULL AUTO_INCREMENT,   `score` int(11) DEFAULT '0',   PRIMARY KEY (`id`),   KEY `k_s` (`score`) ) ENGINE=MyISAM AUTO_INCREMENT=1000001 DEFAULT CHARSET=utf8 ROW_FORMAT=DYNAMIC

1 row in set (0.00 sec)

 

mysql> select count(1) from scores; +----------+ | count(1) | +----------+ |  1000000 | +----------+ 1 row in set (0.00 sec)

 

 

mysql> select id,score,(select count(1) from scores where score>= (select score from scores where id = 100 order by score desc limit 1)) as rank from scores whe re id = 100; +-----+-------+--------+ | id  | score | rank   | +-----+-------+--------+ | 100 |    64 | 370311 | +-----+-------+--------+ 1 row in set (1.05 sec)

 

2、分句完成。效率高。

存储过程：

DELIMITER $$

DROP PROCEDURE IF EXISTS `test`.`sp_rank`$$

CREATE PROCEDURE `test`.`sp_rank`(IN str_id int(11)) BEGIN   -- user's score   DECLARE str_score int;   -- user's rank   DECLARE rank int;   select score from scores where id = str_id order by score desc limit 1 into str_score ;   select count(*) from scores where score >=str_score into rank;   -- output   select id,score,rank from scores where id = str_id; END$$

DELIMITER ;

 

mysql> call sp_rank(100); +-----+-------+--------+ | id  | score | rank   | +-----+-------+--------+ | 100 |    64 | 370311 | +-----+-------+--------+ 1 row in set (1.02 sec)

Query OK, 0 rows affected (1.02 sec)