mysql - SQL SUM 和比较

Question

我有两个数据库表:

***aff_purchases***

id | affiliate_id | payout
1  | 12           | 50.00 
2  | 12           | 10.00
3  | 12           | 50.00
4  | 12           | 10.00

***aff_payments***

id | affiliate_id | amount_paid   
8  | 12           | 50.00

我想返回所有联属成员(member) ID 的数组，其中“付款”总额为 50 或高于联属成员(member) ID 的“已支付金额”。

我认为我需要将各列相加然后进行比较，但我很难理解如何进行。请参阅下面我的努力:

SELECT
     (SELECT SUM(amount_paid) FROM exp_cdwd_aff_payments AS pay WHERE pay.affiliate_id = 12) AS 'amount_paid'
     (SELECT SUM(payout) FROM exp_cdwd_aff_purchases AS pur WHERE pur.affiliate_id = 12) AS 'payout'
FROM 
     exp_cdwd_aff_payments AS pay
WHERE 
     payout > amount_paid

Answer 1

这里的一种方法是使用连接两个单独的子查询来查找支出和付款总额。然后，比较每个 affiliate_id 以查看是否满足您的要求。

SELECT
    t1.affiliate_id
FROM
(
    SELECT affiliate_id, SUM(amount_paid) AS amount_paid_total
    FROM aff_payments
    GROUP BY affiliate_id
) t1
LEFT JOIN
(
    SELECT affiliate_id, SUM(payout) AS payout_total
    FROM aff_purchases
    GROUP BY affiliate_id
) t2
    ON t1.affiliate_id = t2.affiliate_id
WHERE COALESCE(t2.payout_total, 0) > t1.amount_paid_total + 50

请注意，已付款但尚未付款的联营公司不会出现在结果集中。