If I am implementing the database change, I am probably going for SQLite and not implementing a more relational structure but just use it as key-value store probably in the same db layout that is applied by https://docs.python.org/3/library/dbm.html#module-dbm.sqlite3
But I need to address #1095493 first so we can have one database transition in unstable that encompasses both multiple version support from current experimental version and the database library change.
