Re: SQL Sequence use cases

[Luis Rodriguez <luisro58@xxxxxxxxx>]

There are some things not so sensitive to gaps (my main concern). Client
numbers, part numbers, etc. Having a SEQUENCE object is an easy way to make
sure the number does not get duplicated. A common problem with
user-maintained and designed sequence files is that, in some cases, a
program could "Read, Increment, Update" the file and then use the number
while other program could read, use the number, increment and update.

 Regards,

Luis Rodriguez
IBM Certified Systems Expert — eServer i5 iSeries



On Wed, Nov 25, 2009 at 3:50 PM, David Gibbs <david@xxxxxxxxxxxx> wrote:
> On 11/25/2009 2:09 PM, Luis Rodriguez wrote:
> > As per the business cases that David comments, I suppose that this
> > (the sequence object) could be seen as just another tool that SQL
> > provides. Myself, am a little uneasy about the storing of the data in
> > a *DTAARA (something that sometimes gets overlooked when restoring or
> > saving). Also, the fact that I can't get a guarantee of the sequence
> > can give some problems (think, for example, invoice numbers).
>
> I'm not so concerned about the backup / restore issues ... as I always
recommend backing up the entire data library at once.
> The non-sequential nature of a cached sequence makes me wonder what kind
of application it could be used for.
> david
>
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