Hum... Oracle has its service names and SID, MS SQL server has instances, PostgreSQL is actually what you'd expect from a network server, SQLite is obviously completely different from anything else. I don't remember the MySQL connection parameters, but I remember the username is a crazy multi-part string.
And that's just the basic connection parameters, you will want to set some advanced ones once in a while. I don't see what you gain by creating an universal interface, since they are all completely different from each other.
Using a schema that allows you to specify a different parser for the remainder of the string would fix this. Like: sqlite:// and redis://. You could the have standards for common things like usernames, passwords, hosts, ports, and storage path.
And that's just the basic connection parameters, you will want to set some advanced ones once in a while. I don't see what you gain by creating an universal interface, since they are all completely different from each other.