>>Full database update? What's that?

That means, we create an empty database structure, and pump the old
database's datas into this new one.

>>Running a bunch of ALTER TABLE ADD FOREIGN KEY statements should do the
>>job. It isn't much complicated to write a tool that would use the info
>>from system tables to drop all FKs and recreate them later. Which
>>programming language do you use to access Firebird?

In fact this is what we are using. Drop all FKs, and then recreate them with
a full database update.