Object oriented database

I need to implement SQL database with tables storing simple objects
(by "simple objects" I mean objects consisting of simple values, not
containing other objects). However there are several classes and some
classes are derived from other classes. For every class I introduce a
DB table. (So, in a sense, some tables are derived from other tables,
that is either simply have all fields other table have, or refer to
other table by IDs; I don't know which of these two approaches
(duplicate fields or referring by ID) is better.)

Which Perl modules could be used for object-relational mapping in the
case of such base and derived classes corresponding to tables? There
are several object-relational mapping Perl modules. Which is best for
my task?
.