如何把sqlserver中的列转换成行，行转换成列，显示。

create database arron  
go  
use arron  
go  
  
-- createTable init Data  
create table students (  
  name varchar(25),class varchar(25),grade int  
)  
insert into students values ('张三','语文',20)  
insert into students values ('张三','数学',90)  
insert into students values ('张三','英语',50)  
insert into students values ('李四',81)  
insert into students values ('李四',60)  
insert into students values ('李四',90)  
  
-- solution1  
select * from students   
pivot(   
max(grade)   
FOR [class] IN ([语文],[数学],[英语])  
) AS pvt  
  
  
-- solution2 相当于自连接  
  
select A.Name,A.grade as 语文,B.grade as 数学,C.grade as 英语  
from students A,students B,students C  
where A.Name=B.Name and B.Name=C.Name  
and A.class='语文' and B.class='数学'  
and C.class='英语'  
  
-- solution3   
select name,max(case when s.class='语文' then s.grade end) as 语文,max(case when s.class='数学' then s.grade end) as 数学,max(case when s.class='英语' then s.grade end) as 英语  
 from students s group by name  
  
  
--在有id 的情况下  
create table students2 (  
  id int primary key identity(1,1),name varchar(25),grade int  
)  
  
insert into students2 values ('张三',20)  
insert into students2 values ('张三',90)  
insert into students2 values ('张三',50)  
insert into students2 values ('李四',81)  
insert into students2 values ('李四',60)  
insert into students2 values ('李四',90)  
  
-- 原先的solution1(有问题)  
select * from students2   
pivot(   
max(grade)   
FOR [class] IN ([语文],[英语])  
) AS pvt  
-- 原先的solution2 (ok)  
select A.Name,students2 B,students2 C  
where A.Name=B.Name and B.Name=C.Name  
and A.class='语文' and B.class='数学'  
and C.class='英语'  
-- 原先的solution3 （ok）  
select name,max(case when s.class='英语' then s.grade end) as 英语  
 from students s group by name  
  
  
--unpivot 函数使用  
create table test1(id int,name varchar(20),Q1 int,Q2 int,Q3 int,Q4 int)  
insert into test1 values(1,'a',1000,2000,4000,5000)  
insert into test1 values(2,'b',3000,3500,4200,5500)   
  
--实现的sql  
select * from test1  
  
select id,[name],[jidu],[xiaoshou] from test1  
unpivot  
(  
 xiaoshou for jidu in  
 ([q1],[q2],[q3],[q4])  
)  
as f  
  
--- 以下的sql 可以替换上面的sql  
select id,jidu='Q1',xiaoshou=(select Q1 from test1 where id=a.id)  
from test1 as a  
union  
select id,jidu='Q2',xiaoshou=(select Q2 from test1 where id=a.id)  
from test1 as a  
union  
select id,jidu='Q3',xiaoshou=(select Q3 from test1 where id=a.id)  
from test1 as a  
union  
select id,jidu='Q4',xiaoshou=(select Q4 from test1 where id=a.id)  
from test1 as a  

（编辑：李大同）

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