Question

我需要帮助编写此查询以获取类型为401的所有记录，除非最新记录类型为400. ID 16是一个让我失望的记录示例。我确信这很容易而且我在想它但是我已经坚持了几天了。请帮忙。

PK  ID  Type  Changeddate
1   10  400   9/30/15 20:08
2   11  401   10/7/15 18:55
3   11  401   10/7/15 18:55
4   12  400   10/9/15 20:08
5   12  400   10/9/15 20:08
6   13  401   10/14/15 14:12
7   13  401   10/14/15 14:12
8   13  400   10/15/15 15:06
9   13  400   10/15/15 15:06
10  14  401   10/26/15 17:08
11  14  401   10/26/15 17:08
12  15  401   10/29/15 3:48
13  15  401   10/29/15 3:48
14  15  400   10/29/15 19:52
15  16  400   12/29/15 13:04
16  16  400   12/29/15 13:04
17  16  401   12/29/15 13:04
18  16  401   12/29/15 13:04
19  16  400   12/29/15 13:42
20  16  400   12/29/15 13:42

Answer 1

对于SQL Server，您可以使用last_value窗口函数：

select  *
from    (
        select  *
        ,       last_value(Type) over (
                    partition by ID 
                    order by Changeddate
                    rows between unbounded preceding and unbounded following)
                    as last_type
        from    YourTable yt1
        where   Type in (400, 401)
        ) sub
where   last_type <> 400

Example at SQL Fiddle.

SQL查询最大日期值

1 个答案: