Re: Best approach for a "gap-less" sequence

On 8/12/06, Jorge Godoy <jgodoy(at)gmail(dot)com> wrote:
>
> Hi!
>
>
> I was trying to solve a problem on an old system and realized that there might
> be some better approach for doing what I need.
>
> We have some documents that need to be ordered sequentially and without gaps.
> I could use a sequence, but if the transaction fails then when I rollback the
> sequence will already have been incremented.
>
> So, today I have a control table and I acquire a SHARE ROW EXCLUSIVE lock to
> it, read the value, increase it, do what I need and then I COMMIT the
> transaction, ensuring that the sequence has no gaps.
>
> Is there a better way to guarantee that there will be no gaps in my sequence
> if something goes wrong with my transaction?

Why does it matter?

I assume there is a reason you need it like this..

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