oracle distinct 问题

[亲努力啊]

A 表有三个段

id userName time
1 张三 2011-11-04
2 王五 2011-10-15
3 张三 2011-10-22
4 张三 2011-10-17


我想要得结果是 张三 和王五最新的记录

请各位帮忙谢谢

[亲努力啊]

结果也就是这个样子(id 要不要都可):
id userName time
1 张三 2011-11-04
2 王五 2011-10-15

[cnwz]

select id,userName,time
from (
  select id,userName,time
    ,row_number() over (partition by userName order by time desc) RN
  from A
  where A.userName in ('张三','王五')
) B
where RN = 1

[BenChiM888]

SELECT *
  FROM (SELECT ID,
               USERNAME,
               TIME,
               ROW_NUMBER() OVER(PARTITION BY USERNAME ORDER BY TIME DESC) ROW_
          FROM A)
 WHERE ROW_ = 1;

[亲努力啊]

[Quote=引用 3 楼 benchim888 的回复:]
SQL code

SELECT *
FROM (SELECT ID,
USERNAME,
TIME,
ROW_NUMBER() OVER(PARTITION BY USERNAME ORDER BY TIME DESC) ROW_
FROM A)
WHERE ROW……
[/Quote]
谢谢