MYSQL INNER JOIN意外结果

Question

我的MySQL内连接有问题。我的INNER JOIN没有给我我想要的结果。我的 Table1 只包含TrackNo Table2 包含每trackNo Table1 的详细信息。

＆GT;＆GT;表格结构：

＆GT;＆GT; SQL代码：

SELECT tr.trackNo AS 'TrackNo',
       trD.Status,
       MAX(trD.DatePosted) AS `Date/Time`
FROM Tracking AS tr
INNER JOIN TrackingDetails AS trD
ON tr.trackNo = trD.trackNo
WHERE tr.ClientID='client01'
AND trD.trackNo IN ('xx000001','xx000002','xx000003')
AND trD.DatePosted IS NOT NULL 
AND trD.Status IN (
                'Received',
                'Logged',
                'Prepped',
                'Analyzed',
                'Reviewed',
                'Final Report',
                'Invoiced')
GROUP BY tr.trackNo
ORDER BY tr.trackNo ASC

以上是上面的结果查询：

正如您所看到的，上面的查询结果图片是正确的，但Status列除外。我的SQL查询出了什么问题？我错过了什么？

＆GT;＆GT;期望的输出：

+----------+----------+---------------------+
|  TrackNo |  Status  |      Date/Time      |
+==========+==========+=====================+
| xx000001 | Logged   | 2015-03-09 17:53:14 |
+----------+----------+---------------------+
| xx000002 | Prepped  | 2014-08-15 17:19:00 |
+----------+----------+---------------------+
| xx000003 | Analyzed | 2014-10-10 11:12:00 |
+----------+----------+---------------------+

提前致谢！

Answer 1

这应该会给你正确的结果：

select * from TrackingDetails as a join (
    SELECT tr.trackNo AS 'TrackNo',
           MAX(trD.DatePosted) AS 'Date_Time'
    FROM Tracking AS tr
    INNER JOIN TrackingDetails AS trD
    ON tr.trackNo = trD.trackNo
    WHERE tr.ClientID='client01'
    AND trD.trackNo IN ('xx000001','xx000002','xx000003')
    AND trD.DatePosted IS NOT NULL 
    AND trD.Status IN (
                    'Received',
                    'Logged',
                    'Prepped',
                    'Analyzed',
                    'Reviewed',
                    'Final Report',
                    'Invoiced')
    GROUP BY tr.trackNo
    ORDER BY tr.trackNo ASC

) as x on x.TrackNo = a.trackNo and a.DatePosted = x.'Date_Time'

如果在mysql中使用group by，则不会指定从不在聚合函数或group by语句中的列获取的值。在大多数其他DBMS中，不允许选择此类列。