query("SELECT * FROM students where enrollment_no = '".$post['enrollment_no']."'")->fetch_assoc(); $course = $con->query("SELECT * FROM courses where id = '".$get['course_id']."'")->fetch_assoc(); echo $course['course_name'].'|'.$course['id']; // Use $course instead of $c break; case 'get_roll': $get = $con->query("SELECT * FROM students where enrollment_no = '".$post['enrollment_no']."'")->fetch_assoc(); $course = $con->query("SELECT * FROM courses where id = '".$get['course_id']."'")->fetch_assoc(); echo $course['course_name'].'|'.$course['id']; // Use $course instead of $c break; // case 'get_roll': // $enrollmentNo = $post['enrollment_no']; // $student = $con->query("SELECT * FROM students WHERE enrollment_no = '$enrollmentNo'")->fetch_assoc(); // if ($student) { // $courseId = $student['course_id']; // $course = $con->query("SELECT * FROM courses WHERE id = '$courseId'")->fetch_assoc(); // if ($course) { // $return['course_name'] = $course['course_name']; // $return['course_id'] = $course['id']; // } // } // break; } echo json_encode($return); } ?>