例如
A表
user_id name time
33 www 2010-05-06
33 www 2010-06-07
33 www 2010-07-08
44 www 2010-05-07
44 www 2010-06-07查询后
B表
user_id name time
33 www 2010-07-08
44 www 2010-06-07
这SQL怎么写???
即根据user_id把time最大的选出来组成一张表,我第一次接触oracle ,不太会,还请各位高手帮帮忙啊~~~
A表
user_id name time
33 www 2010-05-06
33 www 2010-06-07
33 www 2010-07-08
44 www 2010-05-07
44 www 2010-06-07查询后
B表
user_id name time
33 www 2010-07-08
44 www 2010-06-07
这SQL怎么写???
即根据user_id把time最大的选出来组成一张表,我第一次接触oracle ,不太会,还请各位高手帮帮忙啊~~~
select user_id,name,max(time)
from a
group by user_id,name
create table a
(user_id number(8),
name varchar2(20),
time date);insert into a values(33,'www',to_date('2010-07-08','yyyy-mm-dd'));
insert into a values(33,'www',to_date('2010-06-07','yyyy-mm-dd'));
insert into a values(33,'www',to_date('2010-05-06','yyyy-mm-dd'));
insert into a values(44,'www',to_date('2010-05-07','yyyy-mm-dd'));
insert into a values(44,'www',to_date('2010-06-25','yyyy-mm-dd'));
create table b
(user_id number(8),
name varchar2(20),
time date);insert into b (
select user_id,name,max(time)
from a
group by user_id,name);