Question

我试图找出一种查询表格的有效方法，我需要在两个方向上输出最接近给定日期的行。

我有一个解决方案，为将来最近的一天

SELECT  top 1 id
   FROM [dbo].[Shipments] 
   WHERE EstimatedArrivalDate < @date
   AND Complete = 0 
   AND (RegNoTrailer = @regNo OR RegNoTruck = @regNo) 
   ORDER BY EstimatedArrivalDate DESC

这是最接近的未来日期，但我也需要检查过去的日期。

Answer 1

您可以结合使用Datediff和Abs。

select abs(DATEDIFF(second,<dateColumn>,<dateParameter>)) result,<otherColumns> 
from <tableName> order by  result

第一张唱片将是最接近的唱片。

Answer 2

如果您希望此功能高效，则需要正确的索引。如果是这样，我认为可能是一个更复杂的查询：

SELECT TOP 1 id
FROM ((SELECT TOP 1 id, EstimatedArrivalDate
       FROM [dbo].[Shipments] 
       WHERE EstimatedArrivalDate < @date AND
             Complete = 0 
             RegNoTrailer = @regNo
       ORDER BY EstimatedArrivalDate DESC
      ) UNION ALL
      (SELECT TOP 1 id, EstimatedArrivalDate
       FROM [dbo].[Shipments] 
       WHERE EstimatedArrivalDate < @date AND
             Complete = 0 
             RegNoTruck = @regNo 
       ORDER BY EstimatedArrivalDate DESC
      ) UNION ALL
      (SELECT TOP 1 id, EstimatedArrivalDate
       FROM [dbo].[Shipments] 
       WHERE EstimatedArrivalDate > @date AND
             Complete = 0 
             RegNoTrailer = @regNo
       ORDER BY EstimatedArrivalDate ASC
      ) UNION ALL
      (SELECT TOP 1 id, EstimatedArrivalDate
       FROM [dbo].[Shipments] 
       WHERE EstimatedArrivalDate > @date AND
             Complete = 0 
             RegNoTruck = @regNo 
       ORDER BY EstimatedArrivalDate ASC
      )
     )
ORDER BY ABS(DATEDIFF(second, EstimatedArrivalDate, @Date));

对于此查询，您需要两个索引：Shipments(RegNoTruck, Complete, EstimatedArrivalDate)和Shipments(RegNoTrailer, Complete, EstimatedArrivalDate)。

通过将OR条件拆分为两个单独的子查询，每个子查询可以使用不同的索引。

Answer 3

尝试使用DATEDIFF函数查找2个日期之间的差异。您还需要添加ABS（）函数以满足过去和未来日期

SELECT  top 1 id
   FROM [dbo].[Shipments] 
   WHERE Complete = 0 
   AND (RegNoTrailer = @regNo OR RegNoTruck = @regNo) 
   ORDER BY ABS(DATEDIFF(D,EstimatedArrivalDate,@date)) ASC

Answer 4

这会有用吗？

   SELECT  top 1 id
   FROM [dbo].[Shipments] 
   WHERE EstimatedArrivalDate > @date --change to >
   AND Complete = 0 
   AND (RegNoTrailer = @regNo OR RegNoTruck = @regNo) 
   ORDER BY EstimatedArrivalDate ASC --change to ASC

或两者一起使用UNION

SELECT  top 1 id
   FROM [dbo].[Shipments] 
   WHERE EstimatedArrivalDate < @date
   AND Complete = 0 
   AND (RegNoTrailer = @regNo OR RegNoTruck = @regNo) 
   ORDER BY EstimatedArrivalDate DESC
UNION
   SELECT  top 1 id
   FROM [dbo].[Shipments] 
   WHERE EstimatedArrivalDate > @date --change to >
   AND Complete = 0 
   AND (RegNoTrailer = @regNo OR RegNoTruck = @regNo) 
   ORDER BY EstimatedArrivalDate ASC --change to ASC

Answer 5

使用DATEDIFF（）和ABS（）获取最接近的日期差异

SELECT  top 1 id
   FROM [dbo].[Shipments] 
   WHERE Complete = 0 
   AND (RegNoTrailer = @regNo OR RegNoTruck = @regNo) 
   ORDER BY ABS(DATEDIFF(SECOND, @date, EstimatedArrivalDate))

SQL在两个方向上获取最接近的日期

5 个答案: