sqlserver树形函数汇总

 

if OBJECT_ID('tb','U') is not null drop table tb  

go  

create table tb(ID int,PID INT)  

insert into tb  

select 1,0 union all  

select 2,1 union all  

select 3,2 union all  

select 4,3 union ALL  

select 5,4 union ALL  

select 6,5 union ALL  

select 7,6   

--自定义函数方式实现父节点查询子节点  

if OBJECT_ID('GetChildID') is not null drop function GetChildID  

go  

create function GetChildID(@ParentID int)  

returns @t table(ID int)  

as  

  begin  

     insert into @t select ID from tb where PID=@ParentID  

     while @@rowcount<>0  

     begin  

        insert into @t select a.ID from tb as a   

        inner join @t as b  

        on a.PID=b.ID  

        and not exists(select 1 from @t where ID=a.ID)  

     end  

     return   

  end  

go  

select * from dbo.GetChildID(1)  

--自定义函数方式实现子节点查询父节点  

if OBJECT_ID('GetParentID') is not null drop function GetParentID  

go  

create function GetParentID(@ChildID int)  

returns @t table(PID int)  

as  

  begin  

     insert into @t select PID from tb where ID=@ChildID  

     while @@rowcount<>0  

     begin  

        insert into @t select a.PID from tb as a   

        inner join @t as b  

        on a.ID=b.PID  

        and not exists(select 1 from @t where PID=a.PID)  

     end  

     return   

  end  

go  

select * from dbo.GetParentID(3)  

--公用表表达式实现父节点查询子节点(SqlServer2005+)  

DECLARE @ParentID int  

SET @ParentID=1  

;with CTEGetChild as  

(  

select * from tb where PID=@ParentID  

UNION ALL  

 (SELECT a.* from tb as a inner join  

  CTEGetChild as b on a.PID=b.ID  

 )  

)

SELECT * FROM CTEGetChild  

--公用表表达式实现子节点查询父节点(SqlServer2005+)  

DECLARE @ChildID int  

SET @ChildID=6  

DECLARE @CETParentID int  

select @CETParentID=PID FROM tb where ID=@ChildID  

;with CTEGetParent as  

(  

select * from tb where ID=@CETParentID  

UNION ALL  

 (SELECT a.* from tb as a inner join  

  CTEGetParent as b on a.ID=b.PID  

 )  

)  

SELECT * FROM CTEGetParent  



SELECT * FROM tb