mysql - 如果至少满足一次条件，则将值插入表中

Question

我创建了以下 DataModel:

表客户

INSERT INTO test.customer
(CustomerName, CustomerCountry, RegistrationDate)
VALUES 
("Customer A","DE","2015-05-03"),
("Customer B","US","2015-07-25"), 
("Customer C","US","2016-02-15"), 
("Customer D","DE","2017-09-21"), 
("Customer E","AU","2018-12-07");

表格订单

INSERT INTO test.orders
(idCustomer, PaymentMethod, OrderDate)
VALUES 
("1","CreditCard","2015-05-04"),
("1","PayPal","2015-11-18"), 
("3","PayPal","2017-09-04"), 
("2","Invoice","2018-04-30");

到目前为止一切正常。

---

现在我想根据 WHERE 使用表 Customer 和 Orders 中的值填充表 SpecialCustomers状况。因此，我尝试了以下代码:

INSERT INTO test.specialcustomers
(idCustomer, CustomerName)
SELECT idCustomer, CustomerName
FROM test.customer
LEFT JOIN test.orders ON test.customer.idCustomer = test.orders.idCustomer
WHERE PaymentMethod ="PayPal";

导致错误的原因:

Error Code: 1052. Column 'idCustomer' in field list is ambiguous

据我所知，问题是 Customer A 同时通过 Paypal 和 CreditCard 下了订单，所以 PaymentMethod分配给 Customer A 的 不是唯一的。

但是，我的目标是在至少一次满足条件 时将每个客户插入到表 SpecialCustomers 中。
因此，在上述情况下，如果至少有一个订单是使用 PayPal 支付的，则应将客户插入到表 SpeicalCustomers 中。

我需要在我的代码中更改什么才能使其正常工作？

Answer 1

我认为您只是在选择中缺少别名:

INSERT INTO test.specialcustomers (idCustomer, CustomerName)
SELECT c.idCustomer, c.CustomerName
FROM test.customer c
LEFT JOIN test.orders o
    ON c.idCustomer = o.idCustomer
WHERE o.PaymentMethod = 'PayPal';