基于2列值的最后记录

Question

pass_id retry_id
1       1
1       2
2       1
2       2
2       3
3       1
3       2

需要在MAX（pass_id）内使用MAX（retry_id）获取记录。

pass_id retry_id
3       2

提前致谢！

Answer 1

最简单的方法是使用order by并选择一行：

select t.pass_id, t.retry_id
from (select t.*
      from t
      order by pass_id desc, retry_id desc
     ) t
where rownum = 1

Here是一个SQLFiddle。

Answer 2

SELECT * 
FROM MyTable
WHERE
   retry_id = (Select MAX(retry_id) FROM MyTable) AND 
   pass_id = (Select MAX(pass_id) FROM MyTable)

Answer 3

对oracle语法不是肯定的，但是像

那样

SELECT MAX(retry_ID)
FROM Table
WHERE Pass_ID = (SELECT MAX(Pass_ID)
                 FROM Table)