if exists (select * from SYSTRIGGERS where LCase(trigname)=lcase('TrigReserveDel'))
  then
  drop trigger TrigReserveDel
end if

GO

create TRIGGER "TrigReserveDel" before delete order 1
on "DBA".Reserve
referencing old as RSOLD
for each row
// Premahva wsichki gosti (tabl. "Guests") po rezervaciata, koito niamat
//   wryzka s "Book" ili "ServiceCredits".
begin atomic
  update Guests set Reservation=0
    where Reservation=RSOLD.ReserveNo;
  delete from Guests
    where Reservation=RSOLD.ReserveNo
    and not GuestNum=any(select Guest from Book)
    and not GuestNum=any(select WhoPays from Book)
    and not GuestNum=any(select GuestNo from ServiceCredits)
    and not GuestNum=any(select WhoPays from ServiceCredits)
    and not GuestNum=any(select GuestNo from ResMoney);
end
//[v 00.08.15]