【吐血请教】sql查询语句

[wushuai1346]

求助,查询 (Attr = Length 并且 Value = 6.00000) 并且 (Attr = DIAM 并且 Value = 0.250000) 并且 (Attr = TIP 并且 Value = FLAT) 的 ID_ITEM,我感觉这玩意爆难,要吐血了.求教大神解答，谢过先。不清楚的话尽管问哈。

[裸奔的蜗牛]

楼主 你.......

[哥眼神纯洁不]

select id_item from (select distinct * from 表)a where (Attr = Length and Value = 6.00000) or (Attr = DIAM and Value = 0.250000) or (Attr = TIP and Value = FLAT) group by id_item having count(1)>=3

[wushuai1346]

引用 1 楼 sc273607742 的回复:

select id_item from (select distinct * from 表)a where (Attr = Length and Value = 6.00000) or (Attr = DIAM and Value = 0.250000) or (Attr = TIP and Value = FLAT) group by id_item having count(1)>=3

我了个去,大哥碉堡了,你是怎么做到的?能不能给俺大概讲讲啊,太牛叉了.

[spiritofdragon]

既然都distinct了，就=3就行了。>3也不可能出现。

[哥眼神纯洁不]

引用 3 楼 spiritofdragon 的回复:

既然都distinct了，就=3就行了。>3也不可能出现。

恩，是这样的...

[铁歌]

SELECT DISTINCT ID_ITEM
FROM TABLENAME
(Attr = 'Length' AND Value = 6.00000)
OR (Attr = 'DIAM' OR Value = 0.250000)
OR (Attr = 'TIP' AND Value = 'FLAT')

--算是基础SQL，不需要GROUP BY也行的，GROUP BY是比较消耗CPU的操作，能不用就别用

[唐诗三百首]

select distinct ID_ITEM
 from [表名]
 where (Attr='Length' and Value='6.00000')
    or (Attr='DIAM' and Value='0.250000') 
    or (Attr='TIP' and Value='FLAT')