Question

我正在尝试进行2次LEFT JOINS，SUM结果，减去另一次的总和。一个是正确求和，但是当我放两个连接时，其中一个连接不正确。


    SELECT
    j.jobNumber, j.customerID, j.costDelivery, j.costCallout, j.costLabour , 
    c.customerID, c.firstName, c.lastName , 
    IFNULL(sum(jp.amount),0) AS Total_Paid , 
    IFNULL(j.costDelivery,0) + IFNULL(j.costCallout,0) + IFNULL(j.costLabour,0) + IFNULL(sum(p.unitPrice*p.quantity),0) AS Total_Cost
    FROM s_jobcards AS j 
    INNER JOIN s_customers AS c ON j.customerID = c.customerID 
    LEFT OUTER JOIN s_payments AS jp ON j.jobNumber = jp.jobNumber 
    LEFT OUTER JOIN s_partOrders AS p ON j.jobNumber = p.jobNumber
    GROUP BY j.jobNumber
    HAVING Total_Cost > Total_Paid

Total_Paid列说明jp.amount的总和不正确。但是，Total_Cost正确相加。有什么想法吗？

Answer 1

试试这个：

SELECT j.jobNumber, j.customerID, j.costDelivery, j.costCallout, j.costLabour, 
       c.customerID, c.firstName, c.lastName, IFNULL(jp.payment, 0) AS Total_Paid , 
      (IFNULL(j.costDelivery, 0) + IFNULL(j.costCallout, 0) + IFNULL(j.costLabour, 0) + IFNULL(p.cost, 0)) AS Total_Cost
FROM s_jobcards AS j 
INNER JOIN s_customers AS c ON j.customerID = c.customerID 
LEFT OUTER JOIN (SELECT jp.jobNumber, SUM(jp.amount) payment 
                 FROM s_payments AS jp 
                 GROUP BY jp.jobNumber
               ) AS jp ON j.jobNumber = jp.jobNumber 
LEFT OUTER JOIN (SELECT p.jobNumber, SUM(p.unitPrice * p.quantity) cost 
                 FROM s_partOrders AS p 
                 GROUP BY p.jobNumber
               ) AS p ON j.jobNumber = p.jobNumber 
GROUP BY j.jobNumber
HAVING Total_Cost > Total_Paid;

两个左外连接没有正确求和

1 个答案: