Changes password for user with username. Parameters old_password and new_password should indicate old and new passwords respectively.
成功回傳TRUE失敗回傳FALSE。
備注: In PHP versions before 5.0.0 you must use ocipasswordchange() instead. This name still can be used, it was left as alias of oci_password_change() for downwards compatability. This, however, is deprecated and not recommended.