mysql - 如何编写查询来计算今天的到期金额？

Question

我已经安排付款，所以我有这些表格:

customer
+id

paymentSchedule
+id
+customer_id
+amount  //total price 
+dueDate //date to be paid

payments
+id
+date
+customer_id
+paymentSchedule_id
+amount  //amount paid, it can be a partial payment

如何编写查询来获取客户今天的到期金额。 我的意思是我需要加入表格(这是我的主要问题)，然后减去 payment.mount 的总和减去预定Paymens.amount 的总和 但是..怎么办？ 提前致谢

Answer 1

这可能不是 100%，但应该非常可靠，可以帮助您进行调整:

SELECT customer_id, (due.amount - paid.amount) as amountDue
FROM
    (SELECT customer_id, SUM(amount) as amount 
     FROM paymentSchedule 
     WHERE dateDate <= getDate()
     and customer_id = @custid) as due
   LEFT JOIN
     (SELECT customer_id, SUM(amount) as amount
     FROM payments
     WHERE customer_id = @custid) as paid ON paid.customer_id = due.customer_id