如何在同一表的mysql中按日期時間合並查詢結果？

Question

所有，

我需要您的幫助，以在mysql中的同一datetime中合並結果。

我對兩個表進行查詢 ：

SELECT b.ID, b.DateTime, b.Value 
FROM tableA a, tableB b 
WHERE (a.Id=1) OR (a.Id=2) OR (a.Id=3) AND (a.Id = b.ID) 
      AND (b.DateTime Between '2011-04-02 06:00' And '2011-04-02 06:05')

查詢結果：

| ID  |    DateTime      | Value |
----------------------------------
| 1   | 2011-04-02 06:00 | 20    | 
| 1   | 2011-04-02 06:05 | 21    | 
| 2   | 2011-04-02 06:00 | 10    | 
| 2   | 2011-04-02 06:05 | 16    | 
| 3   | 2011-04-02 06:00 | 23    | 
| 3   | 2011-04-02 06:05 | 22    |

我想要做的就是這樣的結果 ：

|    DateTime      | ID_1    | ID_2   | ID_3   | 
------------------------------------------------
| 2011-04-02 06:00 |  20     |   10   | 23     | 
| 2011-04-02 06:05 |  21     |   16   | 22     | 

我希望對此有解決方案。

在此先感謝您的幫助。

問候，
gy

Answer 1

感謝@liquorvicar提供的解決方案...

我已經嘗試過以下查詢：

SELECT b.Date, 
SUM(CASE WHEN a.Id=1 THEN b.Value ELSE 0 END) AS Mac1, 
SUM(CASE WHEN a.Id=2 THEN b.Value ELSE 0 END) AS Mac2, 
SUM(CASE WHEN a.Id=3 THEN b.Value ELSE 0 END) AS Mac3 
FROM TableA a, TableB b 
WHERE (a.Id = b.ID) AND (b.Date Between '2011-04-02 06:00' And '2011-04-02 06:05') 
GROUP BY b.DA_Date 

結果就像我需要的.. :)