dbplus_resolve() will try to resolve the given
relation_name and find out internal server
id, real hostname and the database path on this host.
Returns an array containing these values under the keys sid, host and host_path or FALSE on error.
This function is EXPERIMENTAL. The behaviour of this function, the name of this function, and anything else documented about this function may change without notice in a future release of PHP. Use this function at your own risk.