oracle 行转列应用

create table student(
sname varchar(20),
sub varchar(20),
score varchar(20)
);

insert into student values('王五','语文','80');
insert into student values('王五','数学','70');
insert into student values('王五','英语','50');
insert into student values('王五','物理','90');
insert into student values('王五','化学','65');
insert into student values('张三','语文','80');
insert into student values('张三','数学','70');
insert into student values('张三','英语','50');
insert into student values('张三','物理','90');
insert into student values('张三','化学','65');
insert into student values('李四','语文','80');
insert into student values('李四','数学','70');
insert into student values('李四','英语','50');
insert into student values('李四','物理','90');
insert into student values('李四','化学','65');

select sname,
       subs,
       REGEXP_SUBSTR(subs, '[^,]+', 1, 5, 'i') 语文,
       REGEXP_SUBSTR(subs, '[^,]+', 1, 2, 'i') 数学,
       REGEXP_SUBSTR(subs, '[^,]+', 1, 4, 'i') 英语,
       REGEXP_SUBSTR(subs, '[^,]+', 1, 3, 'i') 物理,
       REGEXP_SUBSTR(subs, '[^,]+', 1, 1, 'i') 化学
  from (select sname, max(subs) subs
          from (select sname,
                       wmsys.wm_concat(score) over(partition by sname order by sub) subs
                  from student) tabs
         group by sname) tab