sql - Oracle Display the values of columns in single row without using connect by clause -

this query

 select deptno,ename emp_task; 

output

i want output this

eno      ename 20    trinath/rabha 8     saikiran/kishore 10    kumar/vicky/dafni 

select deptno,        listagg(ename,'/') within group (order ename) names temp_task group deptno order deptno;