sql 使用with 递归

 ---前提：有上下级关系的关系表

 ---示例：组织架构表

DECLARE @orgId NVARCHAR(20)='0001';

--向下递归，查询@orgId 下的所有结点。。。包括儿子-孙子节点-到最后的叶子节点

WITH cte

AS

(

SELECT * ,0 AS level FROM dbo.Organization WHERE OrgId=@orgId

UNION ALL

SELECT g.*,level+1 FROM dbo.Organization g INNER JOIN cte

ON g.ParentOrgId=cte.orgId

)

SELECT * FROM cte

 

 

--向上递归，查询@orgId 往上，一直到最根节点

WITH cte

AS

(

SELECT * FROM dbo.Organization WHERE OrgId=@orgId

UNION ALL

SELECT g.* FROM dbo.Organization g INNER JOIN cte

ON g.OrgId=cte.ParentOrgId

)

SELECT * FROM cte