SQL to Convert Column to Rows

create table stu_table(Student varchar2(20),Subject  varchar2(20));
insert into stu_table values('A','Science');
insert into stu_table values('A','math');
insert into stu_table values('A','eng');
insert into stu_table values('B','Science');
insert into stu_table values('B','math');
insert into stu_table values('B','eng');
insert into stu_table values('C','math');
commit;

select * from stu_table;

select STUDENT, SUBJECT,max(student) over(partition by student) stu_GRP
from stu_table;

select SCIENCE, MATH, ENG
from (
select STUDENT, SUBJECT,STUDENT stu_GRP
from stu_table)
pivot(max(student) for subject in ('Science' as Science,'math' as math,'eng' as eng))
order by stu_GRP;


select STUDENT, max(decode(SUBJECT,'Science',STUDENT)) Science,
                max(decode(SUBJECT,'math',STUDENT)) math,
                max(decode(SUBJECT,'eng',STUDENT)) eng
select STUDENT, SUBJECT
from stu_table
group by STUDENT
order by student;

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drop table t;
create table t(id number, val varchar2(30));

insert into t values(1,'amit');
insert into t values(1,'kumar');
insert into t values(1,'sharma');

insert into t values(2,'kishor');
insert into t values(2,'kumar');
insert into t values(2,'prasad');
insert into t values(2,'dev');

insert into t values(3,'siva');
insert into t values(3,'kumar');

commit;


select * from (select id,val,row_number() over(partition by id order by rownum) n_id
from t)
pivot(max(val) for n_id in (1,2,3,4));

SELECT
    id,max(decode(n_id,1,val)) v1,max(decode(n_id,2,val)) v2,max(decode(n_id,3,val)) v3,max(decode(n_id,4,val)) v4
FROM
    (
        SELECT
            id,
            val,
            ROW_NUMBER() OVER(PARTITION BY id ORDER BY ROWNUM) n_id
        FROM
            t
    )
GROUP BY ID;

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