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Question

我有一個表CAD_CHANGES

ID   OBJECT    U_ID     CH_DATE 

1   parcel    20    2017-08-02 15:25:56 
2   parcel    20    2017-08-02 10:31:50 
3   parcel    20    2017-08-02 18:21:45 
4   building    20    2017-08-02 14:03:56 
5   building    20    2017-08-02 12:10:10 
6   parcel    20    2017-08-02 20:21:56 
7   building    20    2017-08-02 21:05:05 
8   parcel    20    2017-08-02 09:14:27 
9   parcel    20    2017-08-02 12:08:15 
10   building    20    2017-08-03 14:09:26 
11   building    20    2017-08-03 11:08:37 
12   building    20    2017-08-03 18:01:48 
13   building    20    2017-08-03 19:05:59 
14   building    20    2017-08-03 21:28:02 
15   building    20    2017-08-03 23:31:05 
16   parcel    20    2017-08-03 09:34:07 
17   parcel    20    2017-08-03 20:21:08 
18   parcel    20    2017-08-03 15:42:04 
19   building    20    2017-08-03 10:51:37 
20   parcel    20    2017-08-03 14:10:22 

我想要得到結果例如

ID    OBJECT    U_ID     CH_DATE 
-------------------------------------------------------------------------- 
3    parcel    20    2017-08-02 18:21:45 
7    building    20    2017-08-02 21:05:05 
--------------------------------------------------------------------------- 
15    building    20    2017-08-03 23:31:05 
17    parcel    20    2017-08-03 20:21:08 

我的表是大隻是我寫的只有兩天，請大家幫忙解決問題， 預先感謝您

（AAA BBB CCC DDD EEE FFF）

Answer 1

喜歡本作例子

SELECT * FROM CAD_CHANGES WHERE (OBJECT, CH_DATE) IN ( 
SELECT OBJECT, MAX(CH_DATE) FROM CAD_CHANGES GROUP BY OBJECT, TRUNC(CH_DATE)) 

或像每個領域的LAST_VALUE分析功能，但是這將是一個小更痛苦