Question

我正在尝试计算数据库中未结清发票的利率。

我正在使用Microsoft Access数据库，但asp.net/C#不喜欢我的更新声明。

asp.net/C#告诉我“查询表达式中存在”附加信息：语法错误（缺少运算符）“。

  "UPDATE s_transaction_enquiry 
   SET s_transaction_enquiry.interest_amount = DateDiff('d', s_transaction_enquiry.due_date, Now()) * (s_transaction_enquiry.payment_amount / 100 * sales_ledger.interest_rate) 
   FROM s_transaction_enquiry JOIN sales_ledger 
   ON s_transaction_enquiry.account_number=sales_ledger.account_number 
   WHERE s_transaction_enquiry.status = 'OPEN';

任何人都可以帮忙纠正这个陈述吗？我认为问题可能在于这一行：

// Im trying to calculate the number of days between today's date and the date in the database.

DateDiff('d', s_transaction_enquiry.due_date, Now())

Answer 1

我认为在MS Access中，当涉及多个表时，SET部分出现在JOIN之后。

尝试这样做

"UPDATE s_transaction_enquiry 
JOIN sales_ledger 
ON s_transaction_enquiry.account_number=sales_ledger.account_number 
SET s_transaction_enquiry.interest_amount = DateDiff('d', s_transaction_enquiry.due_date, Now()) * (s_transaction_enquiry.payment_amount / 100 * sales_ledger.interest_rate) 
WHERE s_transaction_enquiry.status = 'OPEN';"

Answer 2

试试这个：

UPDATE s_transaction_enquiry 
INNER JOIN sales_ledger ON s_transaction_enquiry.account_number = sales_ledger.account_number 
SET s_transaction_enquiry.interest_amount = (DateDiff("d",[s_transaction_enquiry]![due_date],Now())*([s_transaction_enquiry]![payment_amount]/100*[sales_ledger]![interest_rate]))
WHERE (([s_transaction_enquiry]![status]='Open'));

这在Access中运行时没有错误。

SQL Update命令在asp.net C＃中执行计算

2 个答案: