T-SQL:按日期排序,然后分组？

Question

假设我有一个如下所示的数据库表:

ID          name       salary      start_date              city       region
----------- ---------- ----------- ----------------------- ---------- ------
          1 Jason            40420 1994-02-01 00:00:00.000 New York   W
          2 Robert           14420 1995-01-02 00:00:00.000 Vancouver  N
          3 Celia            24020 1996-12-03 00:00:00.000 Toronto    W
          4 Linda            40620 1997-11-04 00:00:00.000 New York   N
          5 David            80026 1998-10-05 00:00:00.000 Vancouver  W
          6 James            70060 1999-09-06 00:00:00.000 Toronto    N
          7 Alison           90620 2000-08-07 00:00:00.000 New York   W
          8 Chris            26020 2001-07-08 00:00:00.000 Vancouver  N
          9 Mary             60020 2002-06-09 00:00:00.000 Toronto    W

是否可以通过start_date降序对其进行排序,然后通过最新的start_date对每个城市组进行排序？例如:

ID          name       salary      start_date              city       region
----------- ---------- ----------- ----------------------- ---------- ------
      9 Mary             60020 2002-06-09 00:00:00.000 Toronto    W
      6 James            70060 1999-09-06 00:00:00.000 Toronto    N
      3 Celia            24020 1996-12-03 00:00:00.000 Toronto    W
      8 Chris            26020 2001-07-08 00:00:00.000 Vancouver  N
      5 David            80026 1998-10-05 00:00:00.000 Vancouver  W
      2 Robert           14420 1995-01-02 00:00:00.000 Vancouver  N
      7 Alison           90620 2000-08-07 00:00:00.000 New York   W
      4 Linda            40620 1997-11-04 00:00:00.000 New York   N
      1 Jason            40420 1994-02-01 00:00:00.000 New York   W

谢谢您的回复.

Answer 1

在SQL Server 2005或更新版本可能是这样的:

select 
  * 
from
  (select *,max(start_date) over(partition by city) max_date from tablename) alias
order by max_date desc, start_date desc

Answer 2

尝试这个：

SELECT * 
FROM
    (
    SELECT 
        *,
        (SELECT MAX(start_date) FROM cities c2 WHERE c1.city = c2.city) AS latest_start_date
    FROM cities c1
    )
ORDER BY latest_start_date DESC, start_date DESC

内部查询会给你这样的结果：

ID          name       salary      start_date              city       region lastest_start_date
----------- ---------- ----------- ----------------------- ---------- ------ -------------------
          1 Jason            40420 1994-02-01 00:00:00.000 New York   W      2000-08-07 00:00:00.000
          2 Robert           14420 1995-01-02 00:00:00.000 Vancouver  N      2001-07-08 00:00:00.000
          3 Celia            24020 1996-12-03 00:00:00.000 Toronto    W      2002-06-09 00:00:00.000
          4 Linda            40620 1997-11-04 00:00:00.000 New York   N      2000-08-07 00:00:00.000
          5 David            80026 1998-10-05 00:00:00.000 Vancouver  W      2001-07-08 00:00:00.000
          6 James            70060 1999-09-06 00:00:00.000 Toronto    N      2002-06-09 00:00:00.000
          7 Alison           90620 2000-08-07 00:00:00.000 New York   W      2000-08-07 00:00:00.000
          8 Chris            26020 2001-07-08 00:00:00.000 Vancouver  N      2001-07-08 00:00:00.000
          9 Mary             60020 2002-06-09 00:00:00.000 Toronto    W      2002-06-09 00:00:00.000