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oracle简单语句

发布时间: 2012-06-05 13:54:06 作者: rapoo

oracle简单语句求助
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~~~

[解决办法]

SQL code
select user_id,name,max(time)from agroup by user_id,name
[解决办法]
SQL code
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 agroup by user_id,name);
[解决办法]
探讨
很详细
SQL code

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','yy……

[解决办法]
select user_id name ,max(time) from A group by user_id
[解决办法]
select user_id ,name,max(time) from a group by user_id;

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