Oracle递归查询父子兄弟节点

1 // 查询id为101的所有后代节点，包含101在内的各级父节点
2 select t.* from SYS_ORG t start with id = '101' connect by parent_id = prior id

1 select t.*
2   from SYS_ORG t
3  where not exists (select 1 from SYS_ORG s where s.parent_id = t.id)
4  start with id = '101'
5 connect by parent_id = prior id

1 select t.*
2   from SYS_ORG t
3  start with id = '401000501'
4 connect by prior parent_id = id

1 select * from SYS_ORG t
2 where exists (select * from SYS_ORG s where t.parent_id=s.parent_id and s.id='401000501')

1 with tmp as(
2       select t.*, level leaf        
3       from SYS_ORG t               
4       start with t.parent_id = '0'     
5       connect by t.parent_id = prior t.id)
6 select *                               
7       from tmp                             
8 where leaf = (select leaf from tmp where id = '401000501');

with tmp as(
    select t.*, level lev
    from SYS_ORG t
    start with t.parent_id = '0'
    connect by t.parent_id = prior t.id)  
select b.*
from tmp b,(select *
            from tmp
            where id = '401000501' and lev = '2') a
where b.lev = '1'
 
union all
 
select *
from tmp
where parent_id = (select distinct x.id
                from tmp x, --祖父
                     tmp y, --父亲
                     (select *
                      from tmp
                      where id = '401000501' and lev > '2') z --儿子
                where y.id = z.parent_id and x.id = y.parent_id);