写一个mysql数据库的sql 递归查询，我现在有个能查询三级的，谁能帮我改为查询四级或五级的

Question

select distinct * from
(select * from news_types where news_types.id=1 union

select n2.* from news_types n1,news_types n2 where n1.id=1 and n2.parentid=n1.id
union select n3.* from news_types n3,(
select n2.* from news_types n1,news_types n2 where n1.id=1 and n2.parentid=n1.id
) t2 where t2.id=n3.parentid) a;
写一个mysql数据库的sql 递归查询，我现在有个能查询三级的，谁能帮我改为查询四级或五级的

Answer 1

又是你啊，昨天的那个不好用么，那个可是无限层的
按照你写的给你改了个5层的
[code="sql"]
select distinct *
from (select *
from news_types
where news_types.id = 1
union
select n2.*
from news_types n1, news_types n2
where n1.id = 1
and n2.parentid = n1.id
union
select n3.*
from news_types n3,
(select n2.*
from news_types n1, news_types n2
where n1.id = 1
and n2.parentid = n1.id) t2
where t2.id = n3.parentid
union
select n4.*
from news_types n4,
(select n3.*
from news_types n3,
(select n2.*
from news_types n1, news_types n2
where n1.id = 1
and n2.parentid = n1.id) t2
where t2.id = n3.parentid) t3
where t3.id = n4.parentid
union
select n5.*
from news_types n5,
(select n4.*
from news_types n4,
(select n3.*
from news_types n3,
(select n2.*
from news_types n1, news_types n2
where n1.id = 1
and n2.parentid = n1.id) t2
where t2.id = n3.parentid) t3
where t3.id = n4.parentid) t4
where t4.id = n5.parentid
) a;

[/code]