sql 行列转换

---行列转换

create table m (
    matid int,
    qty int,
    lid int
)

insert into m values(10011,1,101);
insert into m values(20012,2,102);
insert into m values(10011,2,102);
insert into m values(10011,1,102);

create table l(
    lid int,
    name varchar(20)
)
insert into l values(101,'北京');
insert into l values(102,'太原');


create table s(
    sid int,
    name varchar(20)
)

insert into s values(11,'西服');
insert into s values(12,'皮鞋');


declare @s nvarchar(4000)
set @s=''
select @s=@s+','+quotename(Name)+'=sum(case when m.lid='+rtrim(lid)+' then 1 else 0 end)' from L 
exec('select s.Name as 类别'+@s+'from m inner join s on s.sid=right(m.matid,2) group by s.Name')

学习拓展：http://topic.csdn.net/u/20111018/15/9d404b39-b409-45d0-aae1-d037c25bad46.html?66630