SQL内部联接计算列

Question

我想将销售年至今设置为自动等于帐目代码相等的发票抬头总和。

ALTER TABLE DEBTORS_MASTER  
    ALTER COLUMN Sales_Year_To_Date AS 
          (SELECT SUM (INVOICE_HEADER.Total_Sell_Amount_Excl_VAT)
           FROM DEBTORS_MASTER
           INNER JOIN DEBTORS_MASTER ON INVOICE_HEADER.Account_Code = DEBTORS_MASTER.ACCOUNT_CODE);

我得到这个错误

关键字“ AS”附近的语法不正确

Answer 1

我认为你必须分开做

变更陈述

ALTER TABLE DEBTORS_MASTER
ALTER COLUMN Sales_Year_To_Date INT

更新声明

UPDATE t1
SET Sales_Year_To_Date = Sales_Year_To_Date
FROM DEBTORS_MASTER t1
INNER JOIN (
    SELECT SUM(INVOICE_HEADER.Total_Sell_Amount_Excl_VAT) AS Sales_Year_To_Date
    FROM DEBTORS_MASTER
    INNER JOIN DEBTORS_MASTER ON INVOICE_HEADER.Account_Code = DEBTORS_MASTER.ACCOUNT_CODE
    ) t2 ON t2.ACCOUNT_CODE = t1.ACCOUNT_CODE

Answer 2

您可以使用此代码，

UPDATE DM
SET Sales_Year_To_Date = IH.sumAmount
FROM DEBTORS_MASTER AS DM
INNER JOIN
    (
        SELECT Account_Code, SUM(Total_Sell_Amount_Excl_VAT) sumAmount
        FROM INVOICE_HEADER
        GROUP BY Account_Code
    ) IH
ON IH.Account_Code = DM.Account_Code