SQL Pivot & UnPivot

create table students (
  name varchar(25),
  class varchar(25),
  grade int
)
insert into students values ('ÕÅÈý','ÓïÎÄ',20)
insert into students values ('ÕÅÈý','Êýѧ',90)
insert into students values ('ÕÅÈý','Ó¢Óï',50)
insert into students values ('ÀîËÄ','ÓïÎÄ',81)
insert into students values ('ÀîËÄ','Êýѧ',60)
insert into students values ('ÀîËÄ','Ó¢Óï',90)
select * from students
pivot(
max(grade)
FOR [class] IN ([ÓïÎÄ],[Êýѧ],[Ó¢Óï])
) AS pvt
/*
ÀîËÄ    81    60    90
ÕÅÈý    20    90    50
*/
--=========================================================================
create table students (
  name varchar(25),
  ÓïÎÄ int,
  Êýѧ int,
  Ó¢Óï int
)
GO
INSERT INTO students values ('ÀîËÄ',81,60,90)
INSERT INTO students values ('ÕÅÈý',20,90,50)
select *
from
students
unpivot
(
grade
for class in
([ÓïÎÄ],[Êýѧ],[Ó¢Óï])
) AS upvt
/*
ÀîËÄ    81    ÓïÎÄ
ÀîËÄ    60    Êýѧ
ÀîËÄ    90    Ó¢Óï
ÕÅÈý    20    ÓïÎÄ
ÕÅÈý    90    Êýѧ
ÕÅÈý    50    Ó¢Óï
*/