-- Jalankan satu kali pada database PreJulas yang sudah ada. Cadangkan database terlebih dahulu.
ALTER TABLE users MODIFY role ENUM('admin','guru','orang_tua') NOT NULL DEFAULT 'guru';
CREATE TABLE IF NOT EXISTS parent_students (
 id BIGINT UNSIGNED AUTO_INCREMENT PRIMARY KEY,
 parent_user_id BIGINT UNSIGNED NOT NULL,
 student_id BIGINT UNSIGNED NOT NULL,
 relationship VARCHAR(40) NOT NULL DEFAULT 'Orang Tua/Wali',
 created_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP,
 UNIQUE KEY uq_parent_student(parent_user_id,student_id),
 INDEX idx_parent_student_student(student_id),
 CONSTRAINT fk_parent_students_user FOREIGN KEY(parent_user_id) REFERENCES users(id) ON DELETE CASCADE,
 CONSTRAINT fk_parent_students_student FOREIGN KEY(student_id) REFERENCES students(id) ON DELETE CASCADE
) ENGINE=InnoDB;