这个查询怎么搞，求指导，谢谢
create table Greade(
gid number,
chinese number not null,
match number not null,
english number not null,
primary key (gid)
)
insert into Greade values (1,'45',96,'67');
insert into Greade values (2,'22',76,'45');
insert into Greade values (3,'76',36,'55');

查询的结果要变成 分数小于60 的为不及格 ，大于60 小于80的 为及格，大于等于80的为优秀
例如
gid chinese match english
1 不及格 优秀 及格


求指导，谢谢！ sql
[解决办法]

select gid,
CASE
         WHEN chinese < 60 THEN
          '不及格'
         WHEN chinese < 80 THEN
          '及格'
          ELSE
          '优秀'
       END as chinese,
CASE
         WHEN match < 60 THEN
          '不及格'
         WHEN match  < 80 THEN
          '及格'
          ELSE
          '优秀'
       END as match,
CASE
         WHEN english < 60 THEN
          '不及格'
         WHEN english < 80 THEN
          '及格'
          ELSE
          '优秀'
       END as english
  from Greade; 

[解决办法]
SELECT greade.*,Decode(Sign(greade.english-80),0,'秀',1,'秀',Decode(Sign(greade.english-60),1,'及格',0,'及格','不及格')) FROM greade;
[解决办法]

引用:

select gid,
CASE
         WHEN chinese < 60 THEN
          '不及格'
         WHEN chinese < 80 THEN
          '及格'
          ELSE
          '优秀'
       END as chinese,
CASE
         WHEN match < 60 THEN
          '不及格'
         WHEN match  < 80 THEN
          '及格'
          ELSE
          '优秀'
       END as match,
CASE
         WHEN english < 60 THEN
          '不及格'
         WHEN english < 80 THEN
          '及格'
          ELSE
          '优秀'
       END as english
  from Greade; 

正确 给他70%我要20% 其它平分吧 结贴！