Question

我已经看到许多“ GROUP BY中的N个值”，但是我需要两次。我有：

    CREATE TABLE foo(PK INT(11) NOT NULL, Delivery_Date DATE, Hour_Ending TIME(0), 
                     Resource VARCHAR(26), Rate FLOAT, Submit_Time DATETIME(0), Eff_stop DATETIME(0),  PRIMARY KEY (PK));

insert into foo values(1,'2017-01-04','07:00:00','Plant_BAR','10','2017-01-03 05:00:00','2017-01-03 06:22:00'),
(2,'2017-01-04','07:00:00','Plant_BAR','9','2017-01-03 06:00:00','2017-01-03 06:55:00'),
(3,'2017-01-04','07:00:00','Plant_BAR','10','2017-01-03 06:00:00','2017-01-03 08:22:00'),
(4,'2017-01-04','07:00:00','Plant_BAR','10','2017-01-03 07:55:00','2017-01-03 08:53:00'),
(5,'2017-01-04','07:00:00','Plant_BAzz','50','2017-01-03 13:04:00','2017-01-07 06:22:00'),
(6,'2017-01-04','08:00:00','Plant_BAR','10','2017-01-03 05:00:00','2017-01-03 06:22:00'),
(7,'2017-01-04','07:00:00','Plant_BAzz','55','2017-01-03 05:00:00','2017-01-03 06:22:00'),
(8,'2017-01-04','07:00:00','Plant_BAR','0','2017-01-03 10:00:00','2017-01-03 06:22:00');

我需要一个按时间，资源，交货日期，小时结束时间有效费率的点，这取决于Submit_Time和Eff_Stop。当Subimit_Time对于相同的Resource，Hour_Ending和Delivery_Date相同时，我遇到了问题。

我希望返回max（Submit_Time）行，并且如果有两个相同的提交时间，我希望具有max（Eff_Stop）的行

我有：

SELECT a.PK, a.Delivery_Date, a.Hour_Ending, a.Resource, a.Rate, a.Submit_Time, a.Eff_Stop  
FROM foo as a
INNER JOIN (SELECT Resource, Delivery_Date, Hour_Ending, max(Submit_Time) as max_submit
        FROM foo
        WHERE (Submit_Time < cast(Delivery_Date as datetime)-interval 1 day + interval 7 hour)
                AND (Delivery_Date ='2017-01-04') and (Hour_Ending ='07:00:00')
        GROUP BY Resource, Delivery_Date, Hour_Ending
) as b
ON a.Resource = b.Resource and a.Delivery_Date = b.Delivery_Date and a.Hour_Ending = b.Hour_Ending and a.Submit_Time = b.max_submit
WHERE (a.Delivery_Date ='2017-01-04') and (a.Hour_Ending ='07:00:00')
GROUP BY a.Hour_Ending, a.Delivery_Date, a.Resource;

这使我每个资源返回1行，这是最新的Submit_Time，但是当一个资源具有相同的Submit_Time（在这种情况下为'2017-01-03 06:00:00'）时，我想选择一个与max（Eff_Stop）。

结果是：

PK  Delivery_Date   Hour_Ending Resource    Rate    Submit_Time Eff_stop
2   2017-01-04  07:00:00    Plant_BAR   9   2017-01-03T06:00:00Z    2017-01-03T06:55:00Z
7   2017-01-04  07:00:00    Plant_BAzz  55  2017-01-03T05:00:00Z    2017-01-03T06:22:00Z

我想要：

PK  Delivery_Date   Hour_Ending Resource    Rate    Submit_Time Eff_stop
3   2017-01-04  07:00:00    Plant_BAR   10  2017-01-03T06:00:00Z    2017-01-03T08:22:00Z
7   2017-01-04  07:00:00    Plant_BAzz  55  2017-01-03T05:00:00Z    2017-01-03T06:22:00Z

http://sqlfiddle.com/#!9/5cb999/1/0

我尝试了左右连接，两个内部连接以及一堆其他无效的垃圾。

任何帮助将不胜感激！

Answer 1

我认为这可行：

SELECT a.PK, a.Delivery_Date, a.Hour_Ending, a.Resource, a.Rate, a.Submit_Time, a.Eff_stop  
FROM foo as a
INNER JOIN (SELECT PK, Resource, Delivery_Date, Hour_Ending, Rate, Eff_stop, max(Submit_Time) as max_submit
        FROM foo
        WHERE (Submit_Time < cast(Delivery_Date as datetime)-interval 1 day + interval 7 hour)
                AND (Delivery_Date ='2017-01-04') and (Hour_Ending ='07:00:00')
        GROUP BY Resource, Delivery_Date, Hour_Ending
) as b
ON a.Resource = b.Resource and a.Delivery_Date = b.Delivery_Date and a.Hour_Ending = b.Hour_Ending and a.Submit_Time = b.max_submit
INNER JOIN(SELECT PK, Resource, Delivery_Date, Hour_Ending, Rate, Eff_stop, Submit_Time, max(Eff_Stop) as max_stop
        FROM foo
        WHERE (Submit_Time < cast(Delivery_Date as datetime)-interval 1 day + interval 7 hour)
                AND (Delivery_Date ='2017-01-04') and (Hour_Ending ='07:00:00')
        GROUP BY Resource, Delivery_Date, Hour_Ending, Submit_Time
) as c
ON a.Resource = c.Resource and c.Delivery_Date = a.Delivery_Date and a.Hour_Ending = c.Hour_Ending and a.Eff_Stop = c.max_stop
WHERE (a.Delivery_Date ='2017-01-04') and (a.Hour_Ending ='07:00:00');

在GROUP BY中使用LIMIT在每个组中两次获得N个结果

1 个答案: