Minor Each time we use update_config(), we are doing 2 writes.
An interesting improvement is to check for the current value in the database and write the new one only if needed.
We might win one thread lock and 2 write accesses.
This change implies to review how the row factory is handled. It is spread in a lot of places (each time we ask for a cusor). A simple class atribute and a smarter row assignation will be better use for everyone.
