使用where条件筛选出等于1类、2类的全部,以及包含于3类中的 1 、2 这俩小类 用sql怎么写呀
where (大类 in ('1类','2类') or (大类='3类' and 小类='1'))
where (大类 in ('1类','2类') or (大类='3类' and 小类 in ('1','2')))
where (大类 in ('1类','2类') or (大类='3类' and charindex('1',小类)>0 and charindex('2',小类)>0))
select * from 表 where 类别 in ('1类','2类') or (类别 ='3类' and 小类='1')
select * from 表 where 类别 in ('1类','2类') or (类别 ='3类' and 小类 in ('1','2'))