Massimo,

> > INSERT INTO a (id, a, b, c) VALUES (GEN_ID(A_GEN, 1), 'asdasd',
> 'asdasdasd',
> > 'asdasdasdasd');
> > --- how to access here the current generator value?
>
> select gen_id(A_GEN, 0) as GenValue from RDB$Database

But, please, don't count on that value being the same as the ID field of
the row you have just inserted. In a multiuser environment that isn't
guaranteed.
Ciao
--
____
_/\/ando