Larry,

L> Is there a way to integrate an OPF (Object Persistent Framework) or ORM
L> (Object Relational Mapper) with Firebird?

of course there is. There are many products in these categories that
support Firebird. To name only those that I know directly:
InstantObjects, Hibernate/NHibernate, ECO, tiOPF.

L> I have written an OPF that uses a DAL (Data Access Layer) to support
L> numerous databases.

I am assuming that you have a DAL implementation for each kind of
database, or some kind of "driver" for each kind of database in an
otherwise monolithic DAL. Isn't it?

L> I was contemplating whether I should or could
L> reduce the expense of the OPF by integrating it with the Firebird
L> engine somehow, or reducing the DAL overhead by making direct API
L> calls.

surely you can implement your DAL's interface through Fb API calls.
You need to get acquainted with the Fb API to do that. The range of
options available to you largely depends on what your development
environment is.

Ciao
--
Nando Dessena
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