Estoy intentando ejecutar una subconsulta en Oracle SQL y no me permite ordenar las columnas de la subconsulta. Ordenar la subconsulta es importante ya que Oracle parece elegir a voluntad cuál de las columnas devueltas volverá a la consulta principal.

select ps.id, ps.created_date, pst.last_updated, pst.from_state, pst.to_state,
        (select last_updated from mwcrm.process_state_transition subpst
            where subpst.last_updated > pst.last_updated
            and subpst.process_state = ps.id
            and rownum = 1) as next_response
        from mwcrm.process_state ps, mwcrm.process_state_transition pst
        where ps.created_date > sysdate - 1/24
        and ps.id=pst.process_state
        order by ps.id asc

Really debería ser:

select ps.id, ps.created_date, pst.last_updated, pst.from_state, pst.to_state,
        (select last_updated from mwcrm.process_state_transition subpst
            where subpst.last_updated > pst.last_updated
            and subpst.process_state = ps.id
            and rownum = 1
            order by subpst.last_updated asc) as next_response
        from mwcrm.process_state ps, mwcrm.process_state_transition pst
        where ps.created_date > sysdate - 1/24
        and ps.id=pst.process_state
        order by ps.id asc