比方說,我有一個數據庫表,看起來像這樣:T-SQL:按日期排序,然後分組?
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
有一個簡單的起始日期降序排序這一點,那麼對於每一個城市羣他們通過最新的起始日期?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
謝謝您的回覆。
+1只回答選擇表只有一次 – Andomar 2009-11-06 23:33:03
不要忘記起始日期倒序訂購,MAX_DATE遞減之後。 – 2009-11-07 04:13:39
+1。不知道OVER子句。 – Heinzi 2009-11-07 12:43:24