MySQL 内连接并对两列求和

Question

我有下表

表格:约会

ID | PRICE | PAID
48 |  100  | 180

表格:appointments_products

ID | APPOINTMENT_ID | PRODUCT_ID | TOTAL
10 |       48       |      1     | 30
11 |       48       |      9     | 30
12 |       48       |      6     | 30

我想以某种方式运行一个 MySQL 查询，它将:

a) 连接两个表，对每个appointment_id 的appointments_products 的“TOTAL”求和，如果“PAID”不等于PRICE(来自appointments 表)+ TOTAL(来自appointments_products 表)，则显示它。

这是我到目前为止所做的:

select a.*, b.appointment_id as AppId, b.total as ProdTotal 
from appointments a 
INNER JOIN appointments_products b ON a.id = b.appointment_id

但是这个查询并没有计算每个appointment_id的总数

Answer 1

select a.ID,a.PRICE,a.PAID,a.id as AppId,
       sum(b.total) as ProdTotal 
from appointments a 
INNER JOIN appointments_products b ON a.id = b.appointment_id
group by a.ID,a.PRICE,a.PAID;