--取出点击量最高的文章100篇,每个作者不超过5篇
select top 100 id,title,tips,author
from (
select *,cnt=row_number() over (partition by author order by tips desc)
from tb
) t
where cnt <=5
order by tips desc
--A B 连表 找出对应号码 最大id所对应的公司id select top 1000 a.phone, b.* from dbo.Send_Api a left join ( select SendID , CompanyID , Phone , cnt = row_number() over (partition by phone order by SendID desc) from send ) b on case when len(a.phone)>11 then substring(a.Phone, 3, 11) else a.Phone end=b.phone and b.cnt=1