sql遍历树

oracle有直接的sql来遍历一颗树的子节点和父节点

遍历一个节点的所有子节点（classid的值就是该节点的值）

select *
  from organization_ a
start with a.organizationid = 185137
connect by prior a.organizationid = a.parentorganizationid

遍历一个节点的所有父节点（classid的值就是该节点的值）

select *
  from organization_ a
start with a.organizationid = 185137
connect by  prior a.parentorganizationid=a.organizationid;

主要区别是classid和parentid 的位置