oracle利用游标cursor进行成绩排名

create table tb_score

(

id number(10) not null,

sid varchar2(20) not null,

chinese number(6,2),

maths number(6,2),

english number(6,2),

rank number(10)

);
insert into tb_score values(1,'s0001',100,89,99,null);

insert into tb_score values(2,'s0002',66,58,24,null);

insert into tb_score values(3,'s0003',99,70,33,null);

insert into tb_score values(4,'s0004',46,78,88,null);

insert into tb_score values(5,'s0005',88,89,99,null);

create or replace procedure proc_upd_rank

as

begin

--定义游标

declare cursor cur_rank is

select * from tb_score for update;

--定义总分数

totalScore number(10,2);

--定义名次

v_rank number(10);

begin

for r in cur_rank loop

--获取总分

totalScore:=r.maths+r.chinese+r.english;

--获取名次

select count(*) into v_rank from tb_score

where chinese+maths+english>totalScore;

v_rank:=v_rank+1;

update tb_score set rank =v_rank where current of cur_rank;

end loop;

end;

end;

SQL> call proc_upd_rank();

Method called

SQL> select * from tb_score;

ID SID CHINESE MATHS ENGLISH RANK

----------- -------------------- -------- -------- -------- -----------

1 s0001 100.00 89.00 99.00 1

2 s0002 66.00 58.00 24.00 5

3 s0003 99.00 70.00 33.00 4

4 s0004 46.00 78.00 88.00 3

5 s0005 88.00 89.00 99.00 2