Question

我正在尝试使用例程（cID）通过CustomerID和phpMyAdmin从3个不同的表中删除客户及其订单。我的表结构如下图所示： Tables structure 主键是CustomerID，OrderID，ProductID。

表：订单

OrderID
OrderDate
客户id

表：客户

客户id
客户名称
客户地址

表：产品

的ProductID
ProductDesc
ProductPrice

表：已分配

ProductID（外键）
OrderID（外键）
数量

以下查询：

BEGIN 
INSERT INTO customersdeleted SELECT * FROM customers  
WHERE CustomerID = cID; DELETE assigned 
FROM assigned INNER JOIN orders  
ON assigned.OrderID = orders.OrderID 
WHERE orders.CustomerID = cID;
DELETE FROM customers WHERE customerID = cID; 
SELECT * FROM orders;
SELECT * FROM customers; SELECT * FROM customersdeleted;   
END

我多年来一直试图让这个查询工作，并通过CustomerID删除客户及其订单，并将它们（一旦删除）插入到我也创建的customersdeleted表中。任何帮助将不胜感激！

Answer 1

你在创建表时遇到一些问题; 我给你一个简单的代码解决方案：

create table order(
orderId varchar(10),
order_date date,
customerId char(7),
primary key(customerId)
);
create table customers(
customerId char(7),
customerName varchar(30),
primary key(customerId),
foreign key(customerId) references order(customerId),
on delete cascade

);

N：B：如果从订单表中删除客户ID，删除级联将删除所有表中的customerid。然后更改您的查询，以便您只需删除订单表的customerid，其他人将自动删除因为它们是外键。

Answer 2

我能够使查询正常工作，并将删除的数据添加到特定的表中。在DELETE分配后，我才会失踪，订单。见下文。

BEGIN
INSERT INTO customersdeleted SELECT * FROM customers 
WHERE CustomerID = cID;
DELETE assigned, orders 
FROM assigned
INNER JOIN `orders` ON `assigned`.`OrderID` = `orders`.`OrderID` 
WHERE `orders`.`CustomerID` = cID;
DELETE FROM `customers` WHERE `CustomerID` = cID;
SELECT * FROM orders;
SELECT * FROM customers;
SELECT * FROM assigned;
SELECT * FROM customersdeleted;
END

MySql删除客户＆amp;来自多个表的订单

2 个答案: