SQL 从另一个值为 MIN 值的列中获取一个值

Question

我在 SQL 方面经验不足，我正在尝试从另一个值是最小值的行中获取一个值。我尝试了几件事，但在这个论坛上找不到答案。

我的SQL:

select  
   Name, 
   MIN(StartDateAndTime) as StartTime,
   MAX(EndDateAndTime) as EndTime
from   tblWorkingTimes 
group by Name, 
         convert(date, StartDateAndTime)

所以我有一个 table，其中包含一个 driver 白天完成的所有操作（驾驶、休息、加载...），我想每天做一个总结。每个动作还提供一个 StartPositionText 和 EndPositionText。（例如“ThisStreet 666, 9999 City”）

以上 SQL 有效，但我想添加 StartPositionText 和 EndPositionText。所以我需要从 w.StartDateAndTime = MIN(w.StartDateAndTime) 的行获取 StartPositionText 和行中的 EndPositionText，其中 w.EndDateAndTime = Max(w.EndDateAndTime)。我尝试了 SELECT 但我不能在 WHERE 子句中使用 MIN(w.StartDateAndTime) 并且我无法让它与 HAVING 子句一起使用。

编辑：示例数据 tblWorkingTimes

Name	StartDateAndTime	EndDateAndTime	StartText	EndText
Jim	2021-09-09 07:28:16	2021-09-09 08:28:16	"StartPlace1"	"EndPlace1"
Jim	2021-09-09 08:28:16	2021-09-09 09:28:16	"StartPlace2"	"EndPlace2"
Jim	2021-09-09 09:28:16	2021-09-09 10:28:16	"StartPlace3"	"EndPlace3"
Jim	2021-09-09 10:28:16	2021-09-09 11:28:16	"StartPlace4"	"EndPlace4"

期望的输出

Name	StartDateAndTime	EndDateAndTime	StartText	EndText
Jim	2021-09-09 07:28:16	2021-09-09 11:28:16	"StartPlace1"	"EndPlace4"

提前致谢

Answer 1

您可以为此使用 FIRST_VALUE 和 LAST_VALUE

select  
   w.DriverName, 
   convert(date, w.StartDateAndTime) as DayPerformed,
   MIN(w.StartDateAndTime) as StartTime,
   MAX(w.EndDateAndTime) as EndTime
   StartPositionText,
   EndPositionText
from (
    SELECT *,
      StartPositionText = FIRST_VALUE(StartPositionText) OVER (PARTITION BY w.DriverName, convert(date, w.StartDateAndTime)
            ORDER BY w.StartDateAndTime ROWS BETWEEN UNBOUNDED PRECEDING AND UNBOUNDED FOLLOWING),
      EndPositionText   = LAST_VALUE(EndPositionText) OVER (PARTITION BY w.DriverName, convert(date, w.StartDateAndTime)
            ORDER BY w.StartDateAndTime ROWS BETWEEN UNBOUNDED PRECEDING AND UNBOUNDED FOLLOWING)
    FROM webfleet.tblWorkingTimes w
) w
group by w.DriverName, 
         convert(date, w.StartDateAndTime),
         StartPositionText,
         EndPositionText;

Answer 2

与 Charlieface 类似的 FISRT_VALUE 和 LAST_VALUE 解决方案，但更直接一些。将 CAST 的开始日期和结束日期作为日期添加到分区 by，使用多个日期清理。

DECLARE @t1 TABLE (Driver VARCHAR(50), StartDateTime DATETIME, EndDateTime DATETIME, StartPlace VARCHAR(20), EndPlace VARCHAR(20))

INSERT INTO @t1
VALUES
('Jim','2021-09-09 07:28:16','2021-09-09 08:28:16','    "StartPlace1"','    "EndPlace1"'),
('Jim','2021-09-09 08:28:16','2021-09-09 09:28:16','    "StartPlace2"','    "EndPlace2"'),
('Jim','2021-09-09 09:28:16','2021-09-09 10:28:16','    "StartPlace3"','    "EndPlace3"'),
('Jim','2021-09-09 10:28:16','2021-09-09 11:28:16','    "StartPlace4"','    "EndPlace4"'),
('Jim','2021-09-10 06:28:16','2021-09-10 08:28:16','    "StartPlace1"','    "EndPlace1"'),
('Jim','2021-09-10 08:28:16','2021-09-10 09:28:16','    "StartPlace2"','    "EndPlace2"'),
('Jim','2021-09-10 09:28:16','2021-09-10 10:28:16','    "StartPlace3"','    "EndPlace3"'),
('Jim','2021-09-10 10:28:16','2021-09-10 11:30:16','    "StartPlace4"','    "EndPlace4"')


SELECT DISTINCT
    Driver,
    CAST(StartDateTime AS DATE) AS 'Date',
    FIRST_VALUE(StartDateTime) OVER (PARTITION BY Driver, CAST(StartDateTime AS DATE) ORDER BY StartDateTime  ROWS BETWEEN UNBOUNDED PRECEDING AND UNBOUNDED FOLLOWING) AS StartDateTime,
    LAST_VALUE(EndDateTime) OVER (PARTITION BY Driver, CAST(EndDateTime AS DATE) ORDER BY EndDateTime ROWS BETWEEN UNBOUNDED PRECEDING AND UNBOUNDED FOLLOWING) AS EndDateTime,
    FIRST_VALUE(StartPlace) OVER (PARTITION BY Driver, CAST(StartDateTime AS DATE) ORDER BY StartDateTime ROWS BETWEEN UNBOUNDED PRECEDING AND UNBOUNDED FOLLOWING) AS StartDateTime,
    LAST_VALUE(EndPlace) OVER (PARTITION BY Driver, CAST(EndDateTime AS DATE) ORDER BY EndDateTime ROWS BETWEEN UNBOUNDED PRECEDING AND UNBOUNDED FOLLOWING) AS EndDateTime
FROM @t1

Driver	Date	StartDateTime	EndDateTime	StartDateTime	EndDateTime
Jim	2021-09-09	2021-09-09 07:28:16.000	2021-09-09 11:28:16.000	"StartPlace1"	"EndPlace4"
Jim	2021-09-10	2021-09-10 06:28:16.000	2021-09-10 11:30:16.000	"StartPlace1"	"EndPlace4"

SQL 从另一个值为 MIN 值的列中获取一个值

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