oracle递归树形结构sql

例如：

--向下遍历

select * from tablename  START WITH id=  '111' CONNECT BY PRIOR id=parentid 

--不包含parentid

select * from tablename  START WITH parentid=  '111' CONNECT BY PRIOR id=parentid 

--向上遍历 

select * from tablename  START WITH id=  '111' CONNECT BY PRIOR parentid =id

--不包含parentid

select * from tablename  START WITH parentid=  '111' CONNECT BY PRIOR parentid =id