假设表格为student, 数据如下：

  我们要在MySQL中实现Oracle中的rank()函数功能，即组内排序，具体来说： 就是对student表中按照课程(course)对学生(name)按分数(score)高低进行排名。

  首先新建存储过程realize_rank_in_MySQL，代码如下：

DROP PROCEDURE IF EXISTS realize_rank_in_MySQL;

DELIMITER ;;

CREATE PROCEDURE realize_rank_in_MySQL()

BEGIN

    DECLARE i int;

    SET i = 0;

    WHILE i < (select count(DISTINCT course) from student) DO

            SET @ROW =0;

			INSERT INTO student_rank

			SELECT *, (@ROW:=@ROW+1) AS rank FROM student

			WHERE course=(select DISTINCT course from student limit i,1)

			ORDER BY score DESC;

            set i = i + 1;

    END WHILE;

END

;;

DELIMITER ;

然后输入以下查询语句即可：

drop table if exists student_rank;

create table student_rank like student;

alter table student_rank add rank int;

call realize_rank_in_MySQL;

select * from student_rank;

  结果如下：

注意：这里的排名并没有实现分数相同时排名也一样的情形。