sql取值唯一的方法（SQL 获取所有上级的实现方法）

DECLARE @OrgID NVARCHAR(36)= '00000000-0000-0000-00000002205223459'; 
 
  --获取当前机构的所有上级 放入M0OrgPID 
   WITH  M0OrgPID 
        AS ( SELECT  *, 0 AS lvl 
          FROM   M0Org 
          WHERE  OrgID = @OrgID 
          UNION ALL 
          SELECT  d.*, lvl + 1 
          FROM   M0OrgPID c 
          INNER JOIN M0Org d ON c.PID = d.OrgID ) 
 
     SELECT * FROM  M0OrgPID;