求一条查询语句

[jinning13]

http://community.csdn.net/Expert/topic/4711/4711308.xml?temp=.5246393

麻烦大家帮帮忙，急用！！

[yangshunying]

select b_1.id, b_1.zz, max(b_2.rq)
from b_1,b_2
where b_1.id = b_2.id

[jinning13]

to yangshunying()

如果有这么简单就好了，你先看清楚我要实现的要求

[OracleRoob]

--楼主试试这个

select a.文章id, a.作者, iif(nz(c.更新时间之max,"")="" , a.发表时间,c.更新时间之max) as 最后更新时间
from 表1 as a
left join (select b.文章id, max(b.更新时间) as 更新时间之max from 表2 as b group by b.文章id) as c on a.文章id = c.文章id;

[wwwwb]

SELECT B105L.文章ID, B105L.发表时间, B105L.作者,
IIF(ISNULL((SELECT TOP 1 更新时间 FROM B105M WHERE 文章ID=B105L.文章ID ORDER BY 更新时间 desc )),发表时间,
(SELECT TOP 1 更新时间 FROM B105M WHERE 文章ID=B105L.文章ID ORDER BY 更新时间 desc))
FROM B105L;