WBS

SELECT wbs_id, name, wbs_level, parent_wbs_id, sys_connect_by_path(wbs_id, ' / ') path --sys_connect_by_path(name, ' / ') path
FROM wbs
START WITH parent_wbs_id IS NULL
CONNECT BY prior wbs_id = parent_wbs_id
ORDER siblings BY parent_wbs_id;