Create  TABLE MAIN.[object_group](
[object_title] varchar(50)
,[object_para] varchar(50)
,[group_title] varchar(50)
,[group_value] varchar(50)
, Primary Key(object_title,object_para,group_title,group_value)   
);

Insert  Into [object_group] ([object_title],[object_para],[group_title],[group_value]) Values("桌子","红木八仙桌","品种","家具");
Insert  Into [object_group] ([object_title],[object_para],[group_title],[group_value]) Values("桌子","红木八仙桌","材质","红木");
Insert  Into [object_group] ([object_title],[object_para],[group_title],[group_value]) Values("桌子","红木八仙桌","包装","一类包装-大");
Insert  Into [object_group] ([object_title],[object_para],[group_title],[group_value]) Values("茶几","红木几","品种","家具");
Insert  Into [object_group] ([object_title],[object_para],[group_title],[group_value]) Values("茶几","红木几","材质","红木");
Insert  Into [object_group] ([object_title],[object_para],[group_title],[group_value]) Values("茶几","红木几","包装","二类包装-中");
Insert  Into [object_group] ([object_title],[object_para],[group_title],[group_value]) Values("桌子","平头案","品种","家具");
Insert  Into [object_group] ([object_title],[object_para],[group_title],[group_value]) Values("桌子","平头案","材质","梨花木");
Insert  Into [object_group] ([object_title],[object_para],[group_title],[group_value]) Values("桌子","平头案","包装","一类包装-大");
Insert  Into [object_group] ([object_title],[object_para],[group_title],[group_value]) Values("椅子","电脑转椅","品种","办公");
Insert  Into [object_group] ([object_title],[object_para],[group_title],[group_value]) Values("椅子","电脑转椅","包装","二类包装-中");
Insert  Into [object_group] ([object_title],[object_para],[group_title],[group_value]) Values("椅子","电脑转椅","材质","革");


[object_title] 对象名称
[object_para] 对象参数
[group_title] 组名称
[group_value] 组取值

求查询语句写法：
输入：对象名称，对象参数
输出：和输入对象至少具有两个相同组名称和组取值的其他对象列表
通俗讲，就是：至少有两个分类定义相同的其他物品

也可以扩充为：有若干个分类定义相同

[ 本帖最后由 njy23000 于 2010-11-19 16:48 编辑 ]

太寂寞了。
现已解决，答案如下：
SELECT
  object_title ,
  object_para ,
  count( * ) AS cnt
FROM
  (
    SELECT
      a.group_title ,
      a.group_value ,
      b.object_title ,
      b.[object_para]
    FROM
      MAIN.[object_group] a ,
      object_group b
    WHERE
      a.object_title = '桌子' AND a.object_para = '红木八仙桌' AND a.group_title = b.group_title AND a.group_value = b.group_value AND (
        NOT (
          b.object_title = '桌子' AND b.object_para = '红木八仙桌'
        )
      )
  ) c
GROUP BY
  object_title ,
  object_para ;

cnt表示相同分类定义的计数。扩充也解决了。

呵呵,解决了就好,有时候自己都想想,也能解决的哦!