请教min(),max()等与group by一起的情况

yueliangdao0608

原帖由 sunnyfun 于 2008-3-3 08:58 发表


参见12楼

不好意思，没有仔细看。

willko

牛啊。。
在CSDN看到你，在這里也看到你
以后向你請教問題，請多多幫助

netchecking

小心group by操作的性能极低，应该少使用。呵呵

totomylove

select a.work-id,a.prod_dat,b.* from table_name a left join
(
select work-id as workid,max(prod_num) as maxnum,min(prod_num) as minnum
from table_name
group by work-id
) b
on a.work-id=b.work-id

SWLiu_Unix

select a1.work_id,a1.prod_date as max_date,a1.prod_num as max_num,b1.prod_date as min_date,b1.prod_num as min_num from
(select a.* from table_name as a
where a.prod_num=
(select max(prod_num) from table_name as b
where b.work_id=a.work_id)) as a1
inner join
(select c.* from table_name as c
where c.prod_num=
(select min(prod_num) from table_name  as d
where c.work_id=d.work_id)) as b1
on a1.work_id = b1.work_id

JasonOldWoo

效率还是个问题啊！