ORACLE树查询SQL语句

ORACLE查询树的最大层次：

select max( level)
from pub_classify cf
start with cf.classify_id = 101
connect by prior cf.classify_id = cf.parent_classify_id;

由叶子节点开始的查询

select * from pub_classify cf start with cf.classify_id=30244    
connect by prior cf.parent_classify_id = cf.classify_id;