Re: How to increased by exactly 1 ?

In some European countries gap less sequences for such things as invoices is a legal requirement in accounting software for documents such as invoices. It was a way to make sure that no such documents have been destroyed. Oracle E-Business Suite does offer gap-less sequences, but their use is not recommend as performance really suffers.

In databases I should think that the rationale behind the gap-less sequences can be achieved in other ways such as audit trails on the tables in question. Naïve reimplementation of paper-based procedures does not always make sense.

Even on paper pads with numbered sheets you could go wrong. You could for example spill coffee over them.

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Aleksander Dragnes