Quoting Luke <..hidden..>:
Or is it just because of the gaps? If because of the gaps, then the only invoice numbering possible, is sequential with zero gaps. This no gaps thing is most strange from a U.S. prospective.
It's the gaps. I'll double-check this with my accountant when I see him (sometime in June), but I think that you need to a) explain why you have gaps, and b) demonstrate that the gaps are really gaps, and that you haven't been generating invoices that didn't go through your accounts. I'll come back to the list when I've got a definitive answer.
have a column in ar which is unique and database-incremented, in addition to what is now called the invoice number. Those of use who need a perpetually incrementing invoice number can simply change our templates to use this instead.That is not necessary. The invoice number format is quite configurable. Just set it to "0000000001", and it will increment for ever, with no problems until you have invoiced enough to pay an army of accountants to make it their problem instead of yours.
This is also fine, but it should also be configurable to make the invoice number immutable in the invoice entry form so that someone can't accidentally insert an out of sequence invoice number.
R