mysql子父类关系

CREATE TABLE Product (
    id INT PRIMARY KEY,
    name VARCHAR(255),
    type ENUM('Product', 'ElectronicProduct'),
    price DECIMAL(10, 2)
);

CREATE TABLE Product (
    id INT PRIMARY KEY,
    name VARCHAR(255),
    price DECIMAL(10, 2)
);

CREATE TABLE ElectronicProduct (
    id INT PRIMARY KEY,
    product_id INT,
    brand VARCHAR(255),
    FOREIGN KEY (product_id) REFERENCES Product(id)
);

-- 错误示例
INSERT INTO ElectronicProduct (id, product_id, brand) VALUES (1, 2, 'Apple');

-- 正确示例
INSERT INTO Product (id, name, price) VALUES (2, 'iPhone', 999.99);
INSERT INTO ElectronicProduct (id, product_id, brand) VALUES (1, 2, 'Apple');

-- 添加索引
CREATE INDEX idx_product_id ON ElectronicProduct(product_id);