क्या आपने यह कोशिश की है?
select end_date,
listagg(CLOSE_DATE, ',') within group (order by CLOSE_DATE DESC) as close_dates,
listagg(id, ',') within group (order by id) as ids
from TBL_S_PLCLOSEDATE
where D_END = date '2018-05-18'
group by end_date;