> I am sure there is a simple solution to this, but I am now
> learning my way around Interbase / Delphi and any help would
> be appreciated.

Where is SHOWID from? I presume the table that the stored procedure
is trying to insert into. This would seem to imply that the stored
procedure is not being called with the correct parameter required to
locate the details for the insert.

You may help avoid future problems if you setup your stored procedure
to check for NULL returns when it selects from the source table - and
generates an appropriate exception.

If you start up the SQLMonitor and execute the procedure, you should
be able to see what value is being passed to the procedure which may
well explain the error.

HTH

Geoff Worboys
Telesis Computing