Oracle递归查询

--查询全部资源信息 

select * from urm_class_info 

--向上遍历树，找到路径直到根节点，指定的是parentid 

select distinct classid,parentid,name 

from urm_class_info 

start with parentid = 'cmdb0000000000000017' 

connect by prior parentid = classid 

--向上遍历树，找到路径直到根节点，指定的是classid，和下面的主要区别就是parentid和classid的位置 

select classid,parentid,name 

from urm_class_info 

start with classid = 'cmdb0000000000000401' 

connect by prior parentid = classid 

--向下遍历整棵树，可以指定classid，来遍历指定节点的树 

select classid,parentid,name 

from urm_class_info 

start with classid = 'cmdb0000000000000017' 

connect by prior classid = parentid 

--向下遍历整棵树，可以指定parentid，来遍历指定parentid节点的树，不包含parentid 

select classid,parentid,name 

from urm_class_info 

start with parentid = 'cmdb0000000000000017' 

connect by prior classid = parentid