以图中的dept表为例:
id:主键
parent_id:父id
name:名称
1. 获取所有子节点sql:
selectid from dept where id=2
union
select t.id
from (select * from dept where parent_id is not null) t,
(select @pid :=2) pd
where FIND_IN_SET(parent_id,@pid)>0
and @pid := CONCAT(@pid,',',id)
此sql查询id=2的所有子节点id,并包括当前id=2的节点,如果不想包括当前节点,去掉
selectid from dept where id=2
union
即可
查询结果:
2. 获取所有父节点sql:
SELECT t2.id
FROM ( SELECT @r AS _id, (SELECT @r := parent_id FROM dept WHERE id= _id) AS parent_id,
@l := @l + 1 AS lvl FROM (SELECT @r :=3, @l :=0) vars, dept WHERE @r !=0) t1
JOIN dept t2
ON t1._id = t2.id
ORDER BY t1.lvl DESC
此sql查询id=3的所有父节点sql,
查询结果:
本文转载自: https://blog.csdn.net/scorpio_meng/article/details/131209973
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版权归原作者 scorpio_meng 所有, 如有侵权,请联系我们删除。