Sql 简化/修复长查询

我的问题如下：

SELECT Delivery.DeliveryNumber,
       DeliveryStatus.StatusName,
       Delivery.PickupDateTime,
       Delivery.DeliveryDateTime,
       Delivery.PackageWeight,
       Delivery.PackageSize,
       Delivery.PickupAddress1,
       CASE
           WHEN Delivery.DeliveryDateTime IS NULL THEN 'Not Delivered'
           WHEN (DATEDIFF(hh, Delivery.PickupDateTime, Delivery.DeliveryDateTime) > 0)
                AND (DATEDIFF(hh, Delivery.PickupDateTime, Delivery.DeliveryDateTime) < 24) THEN 'Delivered 24hrs After Pickup'
           WHEN (DATEDIFF(dd, Delivery.PickupDateTime, Delivery.DeliveryDateTime) = 0) THEN 'Delivered Same Day'
       END AS Status
FROM Delivery
INNER JOIN DeliveryStatus ON Delivery.StatusCode = DeliveryStatus.StatusCode

有没有办法清理这个查询

我的任务是设计一个查询，使其返回满足以下条件的行：

已提货交付但尚未交付的包裹 提货后一天内交付的包裹少于24小时 在提货当天交付的包裹 提货前一天在24小时内交付的包裹 我想我问对了。我只是需要帮忙清理一下，因为它看起来很脏。有什么想法吗

编辑：添加了整个数据结构：

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因此，您的问题是，您不希望将同一逻辑编码两次，一次在where子句中，一次在select列表中。您可以通过外部查询从您已有的行中选取所需的行来解决此问题：

SELECT *
FROM 
(
  SELECT Delivery.DeliveryNumber,
         DeliveryStatus.StatusName,
         Delivery.PickupDateTime,
         Delivery.DeliveryDateTime,
         Delivery.PackageWeight,
         Delivery.PackageSize,
         Delivery.PickupAddress1,
         CASE
             WHEN Delivery.DeliveryDateTime IS NULL THEN 'Not Delivered'
             WHEN (DATEDIFF(hh, Delivery.PickupDateTime, Delivery.DeliveryDateTime) > 0)
                  AND (DATEDIFF(hh, Delivery.PickupDateTime, Delivery.DeliveryDateTime) < 24) THEN 'Delivered 24hrs After Pickup'
             WHEN (DATEDIFF(dd, Delivery.PickupDateTime, Delivery.DeliveryDateTime) = 0) THEN 'Delivered Same Day'
         END AS Status
  FROM Delivery
  INNER JOIN DeliveryStatus ON Delivery.StatusCode = DeliveryStatus.StatusCode
)
WHERE Status IS NOT NULL;

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那么COALESCE呢？另外，我认为这里没有很多人能够猜到你的数据结构该死，试图滚动图片。我不明白：当DATEDIFFhh，Delivery.PickupDateTime，Delivery.DeliveryDateTime>0和DATEDIFFhh，Delivery.PickupDateTime，Delivery.DeliveryDateTime<24，然后是“提货后24小时交货”，当DATEDIFFdd，Delivery.PickupDateTime，Delivery.DeliveryDateTime=0时，然后是“当天交货”，因为这里两种逻辑都显示24小时内或当天交货，我认为这是正确的？它应该显示提货后24小时交货，另一个箱子是当天交货。

SELECT *
FROM 
(
  SELECT Delivery.DeliveryNumber,
         DeliveryStatus.StatusName,
         Delivery.PickupDateTime,
         Delivery.DeliveryDateTime,
         Delivery.PackageWeight,
         Delivery.PackageSize,
         Delivery.PickupAddress1,
         CASE
             WHEN Delivery.DeliveryDateTime IS NULL THEN 'Not Delivered'
             WHEN (DATEDIFF(hh, Delivery.PickupDateTime, Delivery.DeliveryDateTime) > 0)
                  AND (DATEDIFF(hh, Delivery.PickupDateTime, Delivery.DeliveryDateTime) < 24) THEN 'Delivered 24hrs After Pickup'
             WHEN (DATEDIFF(dd, Delivery.PickupDateTime, Delivery.DeliveryDateTime) = 0) THEN 'Delivered Same Day'
         END AS Status
  FROM Delivery
  INNER JOIN DeliveryStatus ON Delivery.StatusCode = DeliveryStatus.StatusCode
)
WHERE Status IS NOT NULL;