CREATE TABLE IF NOT EXISTS users (
    id INT AUTO_INCREMENT PRIMARY KEY,
    name VARCHAR(255) NOT NULL,
    email VARCHAR(255) NOT NULL UNIQUE,
    password VARCHAR(255) NOT NULL,
    role ENUM('customer', 'restaurant_owner', 'admin') NOT NULL DEFAULT 'customer',
    created_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP
);

ALTER TABLE restaurants
ADD COLUMN user_id INT,
ADD CONSTRAINT fk_user
FOREIGN KEY (user_id) REFERENCES users(id)
ON DELETE SET NULL;