用主表和子表关联要求取子表登记时间中最大一条! 如题。我主表和子表关联 我想查询出子表中登记时间最大一条 如何写!主表:a (主键bh) 子表:b (子健 a_bh,登记时间:djsj)。 解决方案 » 免费领取超大流量手机卡,每月29元包185G流量+100分钟通话, 中国电信官方发货 select b.a_bh, max(b.djsj) from a left join b on a.bh = b.a_bh group by b.a_bh select b.a_bh, max(b.djsj) from a left join b on a.bh = b.a_bh group by b.a_bh select * from ta a left join (select a_bh,max(djsj) as djsj from tb group by a_bh ) bon a.bh=b.a_bh select * from ta a left join tb b on a.bh=b.a_bhwhere not exists(select 1 from tb c where b.a_bh=c.a_bh and b.djsj<c.djsj) select *from a inner join b t on a.b=t.a_bhwhere not exists (select 1from b where a_bh=a.bh and djsj>t.djsj) oracle 11g dblink 连接只能访问一条数据 SQLplus中没有服务名 oracle存储过程中insert语句性能如何调优? 请问some和any和in那个的效率高? 高手请进,多个oracle服务器的数据同步问题! 关于索引 如何按部门、职位显示/汇总并去除重复列名 很简单的select 语句 可是不知道怎么写 100分 , Oracle表数据导出问题求教 求助! ORA 游标、死锁的问题! trigger自动更新问题
from a
left join b on a.bh = b.a_bh
group by b.a_bh
from a
left join b on a.bh = b.a_bh
group by b.a_bh
(select a_bh,max(djsj) as djsj from tb group by a_bh ) b
on a.bh=b.a_bh
where not exists
(select 1 from tb c where b.a_bh=c.a_bh and b.djsj<c.djsj)
from a inner join b t on a.b=t.a_bh
where not exists (select 1
from b where a_bh=a.bh and djsj>t.djsj)