mysql 修改被关联

-- 创建 users 表
CREATE TABLE users (
    id INT PRIMARY KEY AUTO_INCREMENT,
    name VARCHAR(50)
);

-- 创建 orders 表
CREATE TABLE orders (
    id INT PRIMARY KEY AUTO_INCREMENT,
    user_id INT,
    amount DECIMAL(10, 2),
    FOREIGN KEY (user_id) REFERENCES users(id)
);

-- 插入示例数据
INSERT INTO users (name) VALUES ('Alice'), ('Bob');
INSERT INTO orders (user_id, amount) VALUES (1, 100.00), (2, 200.00);

-- 修改被关联的数据
UPDATE users
SET name = 'Alicia'
WHERE id = 1;

-- 查询修改后的结果
SELECT * FROM orders
JOIN users ON orders.user_id = users.id;

-- 禁用外键检查
SET FOREIGN_KEY_CHECKS = 0;

-- 修改数据
UPDATE users
SET name = 'Alicia'
WHERE id = 1;

-- 启用外键检查
SET FOREIGN_KEY_CHECKS = 1;

CREATE TABLE orders (
    id INT PRIMARY KEY AUTO_INCREMENT,
    user_id INT,
    amount DECIMAL(10, 2),
    FOREIGN KEY (user_id) REFERENCES users(id) ON UPDATE CASCADE
);