Sql行转列问题

[Liao831026]

tb_A:
col1 col2
a 100
aa 300

得到结果
tb_B
a aa
100 200

[jinjazz]

咋就变成了200？

反正都是case when，这个板块相关问题和答案不下1000个了

[百年树人]

select 
  max(case col1 when 'a' then col2 end) as a,
  max(case col1 when 'aa' then col2 end) as aa
from tb_A

[-晴天]

create table tb_A(col1 varchar(10),col2 int)
insert into tb_A select 'a',100 union all select 'aa',300
select top 1 (select col2 from tb_A where col1='a') as a,(select col2 from tb_A where col1='aa') as aa from tb_A
drop table tb_A

[百年树人]

---测试数据---
if object_id('[tb_A]') is not null drop table [tb_A]
go
create table [tb_A]([col1] varchar(2),[col2] int)
insert [tb_A]
select 'a',100 union all
select 'aa',300
 
---查询---
select 
  max(case col1 when 'a' then col2 end) as a,
  max(case col1 when 'aa' then col2 end) as aa
from tb_A


---结果---
a           aa          
----------- ----------- 
100         300

[yygyogfny]

又是行列转换

[you_tube]

http://topic.csdn.net/u/20080614/17/22e73f33-f071-46dc-b9bf-321204b1656f.html