嵌套选择SQL

Question

我有3个表：客户，预订和付款

Customer
---------------
CustomerID
FirstName

Reservation
---------------
ReservationID
CustomerID (FK_Reservation_Customer)

Payment
---------------
PaymentID
ReservationID (FK_Payment_Reservation)

现在我想要选择表格Customer with Reservation to Payment。

Answer 1

您需要JOIN表：

select *
from customer c
inner join reservation r
    on c.customerid = r.customerid
left join payment p
    on r.reservationid = p.reservationid

如果您需要帮助学习JOIN语法，那么有一个很棒的Visual Explanation of SQL Joins会有所帮助。