无限极分类查询

From:http://www.cnblogs.com/smailxiaobai/archive/2012/01/13/2321850.html

 

--建立一个数据表 这可以是你的一个物理表

declare @temp table(

    ID varchar(20),

    ParentID varchar(20),

    Name nvarchar(100))



insert into @temp values('A','','分类A')

insert into @temp values('B','','分类B')

insert into @temp values('C','','分类C')

insert into @temp values('D','','分类D')

insert into @temp values('A1','A','分类A1')

insert into @temp values('A2','A','分类A2')

insert into @temp values('A11','A1','分类A11')

insert into @temp values('A12','A1','分类A12')



select * from @temp



--查询"分类A"下面的所有数据

declare @$result table(

    ID  varchar(20), 

    ParentID  varchar(20), 

    Name nvarchar(100),

    myLevel  int)

declare @Level int

set @Level = 0

insert into @$result select *,@Level from @temp where ID='A'



while(@@rowcount>0)

begin

    set @Level = @Level + 1

    insert into @$result 

    select a.*,@Level 

    from @temp a,@$result b

    where a.ParentID = b.ID and myLevel = @Level-1

end

select * from @$result

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关键就是设一个标志Level进行轮询查找出想要的数据。

查询分类表字段修改成如下：

cataid,catatitle,parentid,orderid





DECLARE @ProductCenterCatalogID int

SET @ProductCenterCatalogID=2;

WITH ACTE(cataid,catatitle,orderid,parentid)

AS

( 

SELECT cataid,catatitle,orderid,parentid

FROM cata WHERE cataid=@ProductCenterCatalogID 

UNION ALL

SELECT TA.cataid,TA.catatitle,TA.orderid,TA.parentid

FROM cata TA INNER JOIN ACTE TB

ON TA.parentid=TB.cataid 

)

SELECT cataid,catatitle,orderid,parentid FROM ACTE order by parentid,orderid

View Code