Retriving data : Rows to column.

Question

Please help in getting the query for the below problem:
There are 2 table DEPT and EMP.I want to get the data "FOR EACH DEPARTMENT ALL THE EMPLOYES SHOULD BE DISPLAYED IN ONE ROW" :
DEPT_ID EMP_NAME
10 JOHN,TINA,RAVI,CHIRS
20 JOE,MIT,MICHALE
30 HARI,KRISHNA,PEMMASANI

Answer 1

Assuming you are on 11.2:
select  deptno,
        listagg(ename,',') within group(order by ename) ename_list
  from  emp
  group by deptno
select  deptno,
        listagg(ename,',') within group(order by ename) ename_list
  from  emp
  group by deptno
    DEPTNO ENAME_LIST
        10 CLARK,KING,MILLER
        20 ADAMS,FORD,JONES,SCOTT,SMITH
        30 ALLEN,BLAKE,JAMES,MARTIN,TURNER,WARD
SQL>For older versions:
select  deptno,
        rtrim(xmlagg(xmlelement(e,ename,',').extract('//text()') order by ename),',') ename_list
  from  emp
  group by deptno
    DEPTNO ENAME_LIST
        10 CLARK,KING,MILLER
        20 ADAMS,FORD,JONES,SCOTT,SMITH
        30 ALLEN,BLAKE,JAMES,MARTIN,TURNER,WARD
SQL>SY.