SQL server 行转列 列转行

Posted 2021-11-02 yanshaoxuan

1.简单案例

　　create database Hang
　　　　go
　　use Hang
　　create table Students
　　(　
　　Name varchar(50),
　　Kemu varchar(50),
　　sor int
　　)
　　insert into Students values(‘张三‘,‘语文‘,8888)
　　insert into Students values(‘张三‘,‘语文‘,85)
　　insert into Students values(‘张三‘,‘数学‘,75)
　　insert into Students values(‘李四‘,‘数学‘,95)
i　　nsert into Students values(‘李四‘,‘语文‘,65)
　　select * from Students

----------------行转列-------------

select * from Students pivot(max(sor) for Kemu in(语文,数学))
as t

----------------列转行----------------
with Lie as (
select * from Students pivot(max(sor) for Kemu in(语文,数学))
as t
)
select *from Lie unpivot (sor for Kemu in(语文,数学))
as t

 

 

2.另一案例

 

 

 

select Name as 水果,
max(case RegionName when ‘北京‘ then Price else 0 end) 北京,
max(case RegionName when ‘广州‘ then Price else 0 end) 广州
from (
select f.Name,r.RegionName,rf.Price from Fruits f
join RegionPrice rf on f.ID =rf.FruitID
join Regions r on rf.RegionID =r.id
) tb group by Name

 

select f.Name,r.RegionName,rf.Price from Fruits f
join RegionPrice rf on f.ID =rf.FruitID
join Regions r on rf.RegionID =r.id

select Name as 水果,
case RegionName when ‘北京‘ then Price else 0 end 北京,
case RegionName when ‘广州‘ then Price else 0 end 广州
from (
select f.Name,r.RegionName,rf.Price from Fruits f
join RegionPrice rf on f.ID =rf.FruitID
join Regions r on rf.RegionID =r.id
) tb

 

select * from
(
select f.Name,r.RegionName,rf.Price from Fruits f
join RegionPrice rf on f.ID =rf.FruitID
join Regions r on rf.RegionID =r.id
) tb
pivot
(
max(tb.Price) for tb.RegionName in
([广州],[北京])
) as a