1、树形结构同级排序
select t.parent_id, t.node_id, level, t.node_order from table_test t
start with t.parent_id = -99999 --起始父节点
connect by t.parent_id = prior t.node_id --本层level的父节点=上一层level的子节点
order siblings by t.node_order; --同级用node_order排序
2、待定