public function registerUser() {
        $CI =& get_instance();

        $result =  $CI->db->query("INSERT Into USERS VALUES ('$this->sp_firstname','$this->sp_lastname','$this->sp_email','$this->sp_password','$this->sp_securityquestion','$this->sp_answer')");
}

public function changePassword() {

        $this->username = $_SESSION['username'];
        $CI =& get_instance();

        $CI->db->query("Update C_Users SET PASSWORD = '$this->updatedPassword' where Email ='$this->username'");

            return true;

    }