Does the AFFECTED command need a local DB?

[kenkendk]

@kees-z

If the affected command only works with access to a valid local database, why is a storage URL required?

The find command uses the storage-URL if no local database is specified to download information directly from the backend.

If affected does not work without a local DB specified, supplying <storage-URL> is redundant, because it will never be used for anything.

Is this a correct assumption?

Yes. There is an “automatic pairing” system for the local database. It can be found in ~/.config/Duplicati.dbconfig.json. The file maps the remote destination (scheme, server, path, port, username) to a database path.

The idea is that the user does not need to type in the --dbpath option, but the correct database is found anyway. I am unsure of well it works in practice. I think some users find it to be a bit too “magical” to rely on it, which is made worse because the UI does not rely on it.

So yes: the storage-url is redundant, if the local database path is supplied. But unless we decide to drop the “magic” pairing, I think we should maintain the format.

@kees-z

Could the affected command retrieve the results in a reasonable amount of time without access to the local database, analyzing the remote files directly like the find command does?

Not really. Without the local database, it would need to download all dlist files, then probably all dindex files to figure out which dblock files belong where. This is essentially the same as rebuilding the local database.