简化 Case When If then 语句答案

【问题标题】：Simplify Case When If then statement简化 Case When If then 语句
【发布时间】：2019-08-02 17:32:36
【问题描述】：

我们的 MIS 提供商向我提供了以下 CASE WHEN 声明。由于我不是专家，我正在考虑简化这一点，所以我越容易阅读，我就越有机会理解和学习。

当前声明：

,CASE SopOrderItem.SoiProcessMethod:WHEN 0 
THEN IF SopOrderItem.SoiReplenishmentOrder 
THEN DO: IF SopProduct.SopPrePostPaid = 0 
THEN ASSIGN lv-ProcessMethod = "Replenishment Pay on Replenishment".
ELSE ASSIGN lv-ProcessMethod = "Replenishment Pay on Delivery".
END.
ELSE lv-processmethod = "Call Off":U.
WHEN 1 THEN lv-processmethod = "On Demand":U.
WHEN 2 THEN lv-processmethod = "Personalised":U.
END CASE

这是我能够写的，我知道我坚持的部分是WHEN SopOrderItem.SoiProcessMethod = 0。在这一点上，我不明白该声明。据我所知，当 SopOrderItem.SoiProcessMethod 为 0 时，检查 SopProduct.SopPrePostPaid 是否也为 0，如果两者都为真，则“补货时付款”，如果不是，则“补货时付款”。

有什么方法可以简化语句，让我更容易理解。

我目前有以下语句，但这导致我的查询失败并需要很长时间才能刷新：

CASE WHEN SopOrderItem.SoiProcessMethod = 1 THEN 'On Demand'
WHEN SopOrderItem.SoiProcessMethod = 2 THEN 'Personalised'
WHEN SopOrderItem.SoiProcessMethod = 0 AND SopProduct.SopPrePostPaid = 0 THEN "Replenishment Pay on Replenishment"
WHEN SopOrderItem.SoiProcessMethod = 0 AND SopProduct.SopPrePostPaid <> 0 THEN "Replenishment Pay on Delivery"
ELSE 'Call Off'
END

【问题讨论】：

标签： sql excel openedge case-when progress-db

【解决方案1】：

我个人会将 CASE 和 IF 分开，而不是将它们合并。但这只会提高可读性。如果这是您依赖这些值的某种查询的一部分，我认为您需要重新考虑它，因为它不会非常有效。

（您需要确保这段代码确实给出了相同的结果 - 如果没有数据并且没有 SopOrderItem + SopProduct 的定义，这有点困难）。

CASE SopOrderItem.SoiProcessMethod:
    WHEN 0 THEN DO :
        IF SopOrderItem.SoiReplenishmentOrder THEN DO:
            IF SopProduct.SopPrePostPaid = 0 THEN
                ASSIGN lv-ProcessMethod = "Replenishment Pay on Replenishment".
            ELSE 
                ASSIGN lv-ProcessMethod = "Replenishment Pay on Delivery".
        END.
        ELSE lv-processmethod = "Call Off":U.
    END.

    WHEN 1 THEN lv-processmethod = "On Demand":U.
    WHEN 2 THEN lv-processmethod = "Personalised":U.
END CASE.

您也可以只设置 IF：

IF SopOrderItem.SoiProcessMethod = 0 THEN DO :
    IF SopOrderItem.SoiReplenishmentOrder THEN DO:
        IF SopProduct.SopPrePostPaid = 0 THEN
            ASSIGN lv-ProcessMethod = "Replenishment Pay on Replenishment".
        ELSE 
            ASSIGN lv-ProcessMethod = "Replenishment Pay on Delivery".
    END.
    ELSE lv-processmethod = "Call Off":U.
END.
ELSE IF SopOrderItem.SoiProcessMethod = 1 THEN lv-processmethod = "On Demand":U.
ELSE IF SopOrderItem.SoiProcessMethod = 2 THEN lv-processmethod = "Personalised":U.

【讨论】：