At 02:55 PM 08-02-02 +0100, you wrote:

>Helen,
>what dangerous situation can happen when maintaining the "own generators values for the auditable series" in a table ... ?

Briefly, in a multi-user situation, without control over the numbers, more than one user can create the next number in the series. It was a long time since this thread was posted (3 months) but the proposed code went something like this:
...
Last_Num = select Max(serialnum) for SerialNumbers;
New_Num = :Last_Num + 1;
Insert into SerialNumbers (serialnum)
values(:New_Num);

or, a variation:

Last_Num = gen_id(gen_SerialNum,0);
New_Num = :Last_Num = 1;
Insert...etc.

or any variations that do similar stuff in a client application...

The original topic was talking about getting serial-numbering with no gaps. The TI paper suggests a technique for achieving this (with auditing of deletions and recycling of "lost" numbers) using a generator. It discusses the multi-user issues....

regards,
Helen


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