固定列数的行列转换
create? table "student"
(
? id number(11,0),
? stuname varchar2(20),
? subject varchar(20),
? grade number(4,2),
? primary key(id)
)
?
insert into "student" values(201001,'javazhou','语文',90);
insert into "student" values(201002,'javazhou','数学',99);
insert into "student" values(201003,'javazhou','英语',80);
insert into "student" values(201004,'xiaoju','语文',90);
insert into "student" values(201005,'xiaoju','数学',70);
insert into "student" values(201006,'xiaoju','英语',98);
select stuname, sum(decode(subject,'语文',grade,null)) "语文" ,
sum(decode(subject,'数学',grade,null)) "数学",
sum(decode(subject,'英语',grade,null))? "英语"
from "student"
group by stuname
?
