Dear Helen

Thanks for your prompt and full reply - I've downloaded your
examples but haven't studied them yet.

I recieved your book One week ago. It's excellent - I'm sure that
it'll be the standard reference on Firebird.

BTW; after studying the section on Referential Integrity and
avoiding setting up a formal Foreign Key constraint on a 'Lookup'
or 'Type' table because of the FK index which is automatically set
up by FB you gave a great example of writting triggers to 'roll your
own' insert and delete routines. How fast does a delete of
the 'linked' table record work after deleting the lookup record
since there's no index on the 'linked' field? I know that in real
life you should probably not delete the lookup record if it is
linked to another table's record.

I'm thoroughly enjoying the whole new learning experience (IBObjects
and Firebird) and your book has added greatly to this

Thanks

Peter