CREATE TABLE IF NOT EXISTS exam_questions (
    id INT AUTO_INCREMENT PRIMARY KEY,
    exam_id INT NOT NULL,
    question_text TEXT NOT NULL,
    question_type ENUM('multiple_choice', 'free_text') NOT NULL,
    options JSON,
    created_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP,
    FOREIGN KEY (exam_id) REFERENCES exams(id) ON DELETE CASCADE
);