使用IF語句更新字段的T-SQL動態更改字段

Question

我們有一個面額表，它存儲每個唯一標識符關鍵字和每個面額的記錄，因此任何給定的唯一標識符關鍵字最多可以有13行，用於指示面額達到該行內有7種不同的交易類型。我可以輕鬆地複製和粘貼下面的查詢（這很好用）7次，每次都使用不同的SET和WHERE子句組合，但這看起來很亂，很長。

查詢：

UPDATE #RecycleCashDenomsClone 
    SET startBal = 
     CASE 
      WHEN B.DenomType = '1.00' THEN A.d_01 
      WHEN B.DenomType = '2.00' THEN A.d_02 
      WHEN B.DenomType = '5.00' THEN A.d_05 
      WHEN B.DenomType = '10.00' THEN A.d_10 
      WHEN B.DenomType = '20.00' THEN A.d_20 
      WHEN B.DenomType = '50.00' THEN A.d_50 
      WHEN B.DenomType = '100.00' THEN A.d_100 
      WHEN B.DenomType = 'C0.01' THEN A.c_01 
      WHEN B.DenomType = 'C0.05' THEN A.c_05 
      WHEN B.DenomType = 'C0.10' THEN A.c_10 
      WHEN B.DenomType = 'C0.25' THEN A.c_25 
      WHEN B.DenomType = 'C0.50' THEN A.c_50 
      WHEN B.DenomType = 'C1.00' THEN A.c_100 
     END 
    FROM #VaultTotals A INNER JOIN #RecycleCashDenomsClone B ON A.importKey = B.importKey 
    WHERE A.identifier = 'D0510' 

我會喜歡做...設置if語句改變@updatedField和@whereField（VARCHAR處理），以7點不同的組合，並將其傳遞到查詢，如下所示：

UPDATE #RecycleCashDenomsClone 
    SET @updatedField = 
     CASE 
      WHEN B.DenomType = '1.00' THEN A.d_01 
      WHEN B.DenomType = '2.00' THEN A.d_02 
      WHEN B.DenomType = '5.00' THEN A.d_05 
      WHEN B.DenomType = '10.00' THEN A.d_10 
      WHEN B.DenomType = '20.00' THEN A.d_20 
      WHEN B.DenomType = '50.00' THEN A.d_50 
      WHEN B.DenomType = '100.00' THEN A.d_100 
      WHEN B.DenomType = 'C0.01' THEN A.c_01 
      WHEN B.DenomType = 'C0.05' THEN A.c_05 
      WHEN B.DenomType = 'C0.10' THEN A.c_10 
      WHEN B.DenomType = 'C0.25' THEN A.c_25 
      WHEN B.DenomType = 'C0.50' THEN A.c_50 
      WHEN B.DenomType = 'C1.00' THEN A.c_100 
     END 
    FROM #VaultTotals A INNER JOIN #RecycleCashDenomsClone B ON A.importKey = B.importKey 
    WHERE A.identifier = @whereField  

不幸的是，這不起作用，沒有錯誤信息，它只是不更新​​字段。如果可能的話，我想避免使用動態SQL，並且像上面提到的那樣，我想避免使用不同的字段和where子句將此查詢複製粘貼7次。

P.S.我測試了這兩個變量varchar（10）並將它們設置爲字符串。 ex./

DECLARE @updatedField VARCHAR(10) = 'startBal' 
DECLARE @whereField VARCHAR(10) = 'D0510' 

Answer 1

這不是一個解決方案，而是一個想法來幫助你。

我不喜歡這個解決方案，因爲大小寫在所有情況下都是相同的，並且每次都更新所有字段。

UPDATE B 
    SET startBal = CASE WHEN @updatedField = 'startBal' THEN 
       CASE 
        WHEN B.DenomType = '1.00' THEN A.d_01 
        WHEN B.DenomType = '2.00' THEN A.d_02 
        WHEN B.DenomType = '5.00' THEN A.d_05 
        WHEN B.DenomType = '10.00' THEN A.d_10 
        WHEN B.DenomType = '20.00' THEN A.d_20 
        WHEN B.DenomType = '50.00' THEN A.d_50 
        WHEN B.DenomType = '100.00' THEN A.d_100 
        WHEN B.DenomType = 'C0.01' THEN A.c_01 
        WHEN B.DenomType = 'C0.05' THEN A.c_05 
        WHEN B.DenomType = 'C0.10' THEN A.c_10 
        WHEN B.DenomType = 'C0.25' THEN A.c_25 
        WHEN B.DenomType = 'C0.50' THEN A.c_50 
        WHEN B.DenomType = 'C1.00' THEN A.c_100 
       END 
      ELSE startBal END 
      ,startBal1 = CASE WHEN @updatedField = 'startBal1' THEN 
       CASE 
        WHEN B.DenomType = '1.00' THEN A.d_01 
        WHEN B.DenomType = '2.00' THEN A.d_02 
        WHEN B.DenomType = '5.00' THEN A.d_05 
        WHEN B.DenomType = '10.00' THEN A.d_10 
        WHEN B.DenomType = '20.00' THEN A.d_20 
        WHEN B.DenomType = '50.00' THEN A.d_50 
        WHEN B.DenomType = '100.00' THEN A.d_100 
        WHEN B.DenomType = 'C0.01' THEN A.c_01 
        WHEN B.DenomType = 'C0.05' THEN A.c_05 
        WHEN B.DenomType = 'C0.10' THEN A.c_10 
        WHEN B.DenomType = 'C0.25' THEN A.c_25 
        WHEN B.DenomType = 'C0.50' THEN A.c_50 
        WHEN B.DenomType = 'C1.00' THEN A.c_100 
       END 
      ELSE startBal1 END 
    FROM #VaultTotals A INNER JOIN #RecycleCashDenomsClone B ON A.importKey = B.importKey 
    WHERE A.identifier = @whereField