Re: Transactions and insertion ordering

nextval() should return value in the order they were called, rather
than commit time. I hope you're not relying on the unordered results of
a table scan remaining stable. Tables have no intrinsic "order", only
one inposed by an external sequence.

Hope this helps,

On Thu, Jun 10, 2004 at 09:28:50AM +0100, James Pharaoh wrote:
> Hi,
>
> I'm trying to work out how to make sure things are read from a table in
> a consistent order. The table represents a queue of items and also the
> history of those items.
>
> Even with "serializable" transaction isolation I can begin two
> transactions, insert a record in each, commit the second transaction
> first. This second record is now visible and can be read from the queue.
> But when I commit the first this one appears before the second one. This
> could then be read from the queue second but when I rescan the table to
> view history it looks like it was read first.
>
> Are there any ways to make this work a little more intuitively?
> Basically I guess I want to be able to model a queue effectively.
>
> James
>
>
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Martijn van Oosterhout <kleptog(at)svana(dot)org> http://svana.org/kleptog/
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