+ case mnesia:backup(mnesia:system_info(directory) ++ "/backup" ++ integer_to_list(Version)) of
+ ok ->
+ patch(Version),
+ update(Version + 1);
+ {error, Raison} -> {error, lists:flatten(io_lib:format("Erreur de création du backup de la version ~w : ~w", [Version, Raison]))}
+ end.