This is partly related to the proposal for including PostgreSQL, but I see other suggestions on the horizon, like Percona. With the eventual introduction of alternative database engines, there will undoubtedly be a need for this feature (mentioned in the title). It might be wise to consider this even before introducing alternative database engines.
It would be a frustrating limitation if the database role were restricted to a single database engine, as it currently is. The simplest use case would be that if we use both PostgreSQL and MariaDB, we’d be forced to have two separate servers. Additionally, sites that rely on PostgreSQL would be limited in migrating to other servers that also specifically have the DB role with PostgreSQL, which, from a management point of view, sounds like a nightmare.
