Question

我正在尝试使用此查询获取日期时差：

SELECT BASESCORE, 
       Max(CONVERT(DATETIME, '')) - Min(CONVERT(DATETIME, '')) AS datediff 
FROM   log 
GROUP  BY BASESCORE 
ORDER  BY BASESCORE

它运作正常，但它给出了我的错误：

   1900-01-01 00:00:00.000
   1900-01-01 00:00:00.000
   1900-01-01 00:00:00.000
   1900-01-01 00:00:00.000
   1900-01-01 00:00:00.000
                    ......

如何从上述查询中获得正确的结果！

Answer 1

正如@Nithesh所说，尝试使用DATEDIFF -

DECLARE @temp TABLE(
       [datetime] DATETIME
     , basescore INT
)

INSERT INTO @temp
VALUES
     ('20130320 03:17:43', 1),
     ('20130320 03:17:43', 2),
     ('20130320 04:17:43', 1),
     ('20130320 03:20:43', 2)

SELECT
       basescore
     , [datediff] = CONVERT(
                         VARCHAR(10), 
                         DATEADD(ms, 
                         DATEDIFF([second], MIN([datetime]), MAX([datetime])) * 1000, 
                    0), 114)
FROM @temp
GROUP BY basescore
ORDER BY basescore

输出 -

basescore   datediff
----------- ----------
1           01:00:00:0
2           00:03:00:0

Answer 2

使用您发布的样本数据（并稍微调整一下），这是我尝试解决问题的方法：

SELECT BASESCORE, 
       Datediff(dd, MINDATE, MAXDATE) 
FROM   (SELECT BASESCORE, 
               Cast(Max(DATETIME) AS DATETIME) MaxDate, 
               Cast(Min(DATETIME) AS DATETIME) MinDate 
        FROM   table1 
        GROUP  BY BASESCORE)T

您可以查看SQL Fiddle上的完整工作版本。

让我知道是否有一些我误解的东西; - ）

Answer 3

之前您向您展示了dateformat，您再次删除了该格式，但我有时间复制它。在我看来，这是您想要的查询和结果：

declare @t table(datetime char(20), basescore int)
insert @t values('20/Mar/2013:03:17:43', 1),('20/Mar/2013:03:17:43', 2)
                ('20/Mar/2013:04:17:43', 1),('20/Mar/2013:03:20:43', 2)

SELECT basescore,  MAX(convertdate) - MIN(convertdate) AS datediff
-- when selecting from your own table remove '@t' from next line
FROM @t log
cross apply(select cast(stuff([datetime], 12, 1, ' ') as datetime) convertdate) a
group by basescore order by basescore

结果：

basescore   datediff
1   1900-01-01 01:00:00.000
2   1900-01-01 00:03:00.000

Answer 4

使用DATEDIFF()。

语法：DATEDIFF(datepart,startdate,enddate)

msdn

Answer 5

我上次从您的帖子编辑中看到，来自字段日期时间的值，例如＆＃39; 20 / Mar / 2013：03：17：44＆＃39;。日期时间值的格式无法通过简单的方式进行转换。

尝试此查询：

SELECT BASESCORE, 
       [DATEDIFF]= Datediff(second, Min(CONVERT(DATETIME, 
                                        LEFT(Rtrim(Ltrim(DATETIME)), 
                                        11) + ' ' 
                                        + RIGHT(Rtrim(Ltrim(DATETIME) 
                                        ), 8))), Max 
                               ( 
                               CONVERT(DATETIME, LEFT(Rtrim(Ltrim(DATETIME)), 11 
                                                 ) + ' ' 
                                                 + RIGHT(Rtrim(Ltrim(DATETIME)), 
                                                 8)))) 
FROM   temptabel 
GROUP  BY BASESCORE 
ORDER  BY BASESCORE

输出：

Basescore    datediff
1            1
2            0
3            0

您可以在SQLFiddle

看到

无法减去日期SQL Server

5 个答案: