用另一个表中的查询删除一个表中的行

Question

我在我的数据库中有两个表。

表客户提供ID，名字，姓氏，地址......

和表订单ID，idCustomer ...

，我想删除客户的所有订单，其中的第一个名字是“约翰”

我如何编写命令？

感谢

Answer 1

DELETE o 
FROM  Orders o 
INNER JOIN Customer c ON o.idCustomer = c.ID 
WHERE  c.firstName = 'john' 

Answer 2

Delete From 
    orders 
Where 
    Orders.firstName In 
     (Select 
      firstName 
     From 
      customers 
      Inner Join orders On customers.ID = orders.idCustomer 
     Where 
      customers.firstName = "john")