Hierarchical Query

 

函数：
sys_connect_by_path(column, separator)

伪列：
connect_by_isleaf
connect_by_iscycle 只有当connect by 有 nocycle 关键字时，才可用

运算符：

prior
connect_by_root(column)

关键字：
start with
connect by [nocycle] prior

 

参考：

Hierarchical Queries
http://docs.oracle.com/cd/E11882_01/server.112/e26088/queries003.htm#i2053935