Re: Transactions: good or bad?

"Todd Bandrowsky" <anakin_at_unitedsoftworks.com> wrote in message news:af3d9224.0305050819.2b2ffe4c_at_posting.google.com...
> I'm going to make the argument that the statement "transactions are
> not compatible with the arrow of time" misses the point of what
> transactions are for.

You go for it Todd.

> In a multiuser system, serialized transactions are the only way to
> accurately ensure that multiple users produce a consistent and
> accurate history of events.

I would prefer to say:

    In a multiuser system, serialized **actions** are the only way to accurately ensure that multiple users produce a consistent and accurate history of events.

> The big point that people debate, really, about transactions, are:
>
> a) Does the history have to be that exact, and,
>
> b) is the price to pay for that accurate history worth it?

So this is a correctness vs performance trade off?

I'm afraid that I am working at the logical level, and will not countenance a logical model that is not correct. Also I would not want to go the route of modelling historical inexactness in my logical model (and thus making such 'inexactness' correct) until I am convinced that a model with historical exactness cannot be physically implemented, today or in the future, in a significant percentage of applications.

> I for one think that in the future we will see more domain specific
> database servers that make use of business knowledge in the domain
> they serve to schedule operations more effectively.

My guess is that you will find yourself mostly alone in that belief.

Semantic optimisation is a general ability of any well implemented RDMBS. Semantic optimisation is exactly the case of using specific 'business knowledge' to optimise DBMS performance.

Regards
Paul Vernon
Business Intelligence, IBM Global Services Received on Tue May 06 2003 - 18:46:27 CEST