Bob Pawley wrote:
> Your missing the point.
>
> I am creating a design system for industrial control.
>
> The control devices need to be numbered. The numbers need to be
> sequential. If the user deletes a device the numbers need to
> regenerate to again become sequential and gapless.
Could you explain what it is about industrial control that requires the
reassignment of numbers? Seems to me to make for confusion because over
time, you then have a particular instrument referred to by different
identifiers. So if you had other data, such as written logs, shop floor
design diagrams, or other data not included in the data base, for
example, you'ld have the problem of keeping track of which instruments
were really being talked about because the names (identifying number,
that is) keep changing.