Query to convert Row to column - Re-posting

Question

Hi all,
i am re-posting the same requirement, please do the needful.
I need a query to convert row value into column delimited by ','
create table tb_row_2_col (id number,val varchar2(100));
insert into tb_row_2_col values (1,'col1');
insert into tb_row_2_col values (1,'col2');
insert into tb_row_2_col values (1,'col3');
insert into tb_row_2_col values (2,'col4');
insert into tb_row_2_col values (2,'col5');
commit;
SQL> select * from tb_row_2_col;
ID VAL
1 col1
1 col2
1 col3
2 col4
2 col5
SQL>
if i execute a query the output should be like this
ID VAL
1 col1,col2,col3
2 col4,col5
Thanks in advance
S. Sathish Kumar

Answer 1

Most repeated question in the forum..
SQL> select id,max(ltrim(sys_connect_by_path(val,','),',')) res
  2  from (select id,val,
  3           row_number() over(partition by id order by val) rn
  4        from tb_row_2_col)
  5  start with rn = 1
  6  connect by prior rn = rn -1
  7          and prior id = id
  8  group by id;
        ID RES
         1 col1,col2,col3
         2 col4,col5<br>
Message was edited by:
jeneesh
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