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BOM 创建用户定义函数,每个子节点de父节点的信息

2010-01-04 21:07  曾祥展  阅读(673)  评论(0编辑  收藏

--生成测试数据
createtable BOM(ID int,parentID int,sClassName varchar(10))
insertinto BOM values(1,0,'1111'      )
insertinto BOM values(2,1,'1111_1'    )
insertinto BOM values(3,2,'1111-1-1'  )
insertinto BOM values(4,3,'1111-1-1-1')
insertinto BOM values(5,1,'1111-2'    )

go

--创建用户定义函数,每个子节点de父节点的信息
createfunction f_getParent(@IDint)
returnsvarchar(40)
as
begin
   
declare@retvarchar(40)

   
whileexists(select1from BOM where ID=@IDand parentID<>0)
   
begin
       
select@ID=b.ID,@ret=','+rtrim(b.ID)+isnull(@ret,'')
       
from
            BOM a,BOM b
       
where
            a.ID
=@IDand b.ID=a.parentID
   
end
   
   
set@ret=stuff(@ret,1,1,'')
   
return@ret
end
go

--执行查询
select ID,isnull(dbo.f_getParent(ID),'') as parentID from BOM
go

--输出结果
/*

ID          parentID                                
----------- ----------------------------------------
1          
2           1
3           1,2
4           1,2,3
5           1  
*/

--删除测试数据
dropfunction f_getParent
droptable BOM
go