Oracle对树形结构按级次排序SQL

1、自顶向下查找

select t.name, t.id

from tree t

start with t.id = 'top'

CONNECT BY PRIOR t.id = t.parent_id

order SIBLINGS by t.order_no

2、自底向上查找

select t.name, t.id

from tree t

start with t.id = 'top'

CONNECT BY PRIOR t.parent_id = t.id

order SIBLINGS by t.order_no