Hi Martijn,

>Keep the trigger, but modify it slightly so that it will only assign a new
>value if there's no value for the ID column. Why? Well, if, for some
>reason, any application starts inserting new rows into that table, at
>least the new records will have IDs. If you don't want this, remove
>the trigger.

My trigger was already testing for null or zero after reading the Firebird
Generators white paper yesterday. The ID field is a PK so it can't be null
or duplicated so I suppose the trigger is mostly redundant with the
modifications you showed me, but I'll leave it just in case.

Many thanks for your help. Your changes make perfect sense.

Cheers,
Rik