Rose::DB is a wrapper and abstraction layer for DBI-related
functionality.  A Rose::DB object "has a" DBI object; it is not a
subclass of DBI.

Please see Rose::DB::Tutorial for an example usage scenario that
reflects "best practices" for this module.

Are you looking for an object-relational mapper (ORM)?  If so,
please see the Rose::DB::Object module.  Rose::DB::Object is an ORM
that uses this module to manage its database connections.  Rose::DB
alone is simply a data source abstraction layer; it is not an ORM.
