多個計算

Question

我試圖讓下面的SQL代碼的工作，但是我正與找出如何做多個計算與case語句掙扎，這裏是代碼：

SELECT 
dbo.Table1.PrimaryKeyID, 
    CASE 

     WHEN (number1 >0 AND number2 = 0) 
      THEN number1 = number1 + CalcView.Quantity 

     WHEN (number1 =0 AND number2 <=0) 
      THEN number3 = number3 + CalcView.Quantity, 
        number2 = number2 - CalcView.Quantity 

     WHEN (number1 =0 AND number2 >0) 
      THEN number3 = number3 + number2 
        number1 = number1 + (CalcView.Quantity - number2) 
        number2 = 0 
END 
FROM Table1 
INNER JOIN CalcViewON Table1.PrimaryKeyID= CalcView.PrimaryKeyID 
WHERE Table1.PrimaryKeyID= CalcView.PrimaryKeyID 

• 的看法是目前擺脫SUM（）的這會強迫我用GROUPBY
• 的名稱是不是我用的，我已經改變了他們更容易underst和..

正如你可以看到我剛纔把THEN內計算的那一刻，請任何人都可以點我如何得到這個說法的工作方向是正確的？三江源任何幫助，您可以給我

例子：

Case 1 
Number1 = 5 
Number2 = 0 
CalcView.Quantity = 3 

5 = 5 + 3 (8) 


Case 2 
Number 1 = 5 
Number 2 = 3 
Number 3 = 2 
CalcView.Quantity = 3 

2 = 2 + 3 (5) 
3 = 3 - 3 (0) 


Case 3 
Number 1 = 5 
Number 2 = 3 
Number 3 = 2 
CalcView.Quantity = 6 

2 = 2 + 3 (5) 
1 = 1 + (6 – 3) (4) 
Number2 = 0 

的宗旨：立足3個WHEN語句來更新數字1，數字和number3的。目前我正在使用select語句來確保我實現了正確的輸出...

CASE語句有哪些替代方法可以幫助我實現目標？再次感謝

Answer 1

您正在試圖計算number1，number2和number3使用單一CASE...WHEN...END聲明，這將無法工作 - 你需要3個不同的case語句。

如果我理解你的邏輯，這應該這樣做

SELECT 
dbo.Table1.PrimaryKeyID, 
    CASE 
    WHEN (number1 >0 AND number2 = 0) 
     THEN number1 + CalcView.Quantity 
    WHEN (number1 =0 AND number2 >0) 
     THEN number1 + (CalcView.Quantity - number2) 
    ELSE 
     number1 
    END AS number1, 
    CASE 
    WHEN(number1 =0 AND number2 <=0) 
     THEN number2 - CalcView.Quantity 
    WHEN (number1 =0 AND number2 >0) 
     THEN 0 
    ELSE 
     number2 
    END AS number2, 
    CASE 
    WHEN (number1 =0 AND number2 <=0) 
     THEN number3 + CalcView.Quantity 
    WHEN (number1 =0 AND number2 >0) 
     THEN number3 + number2 
    ELSE 
     number3 
    END AS number3 
FROM Table1 
INNER JOIN CalcViewON Table1.PrimaryKeyID= CalcView.PrimaryKeyID 
WHERE Table1.PrimaryKeyID= CalcView.PrimaryKeyID