CREATE TABLE vouchers (
    voucher_id INT PRIMARY KEY AUTO_INCREMENT,
    user_id INT NOT NULL,
    product_id INT NOT NULL,
    value DECIMAL(10, 2) NOT NULL,
    date_created TIMESTAMP DEFAULT CURRENT_TIMESTAMP,
    FOREIGN KEY (user_id) REFERENCES users(user_id) ON DELETE CASCADE,
    FOREIGN KEY (product_id) REFERENCES products(product_id) ON DELETE CASCADE,
    INDEX idx_user_id (user_id),
    INDEX idx_product_id (product_id),
    INDEX idx_date_created (date_created)
);