The level of isolation for an "select" depends on the "transaction
isolation" thingy you can set in various ways, depending on the
component set you're using.

Take a look here:
http://www.ibobjects.com/ibo_help/transactionisolation.htm
It's for IBO but you'll understand it, even if you're not using IBO.

--
Cosmin Prund

--- In firebird-support@yahoogroups.com, "Daniel
Albuschat" <d.albuschat@...> wrote:

>
> Hello there,
>
> I have some rather basic questions about transaction semantics.
> I haven't put much thoughts on this topic, because it basically
> 'just worked' for me, but I'd like to understand how things work

now.

> Imagine the following case:
>
> Transaction -> Start
> Select -> Execute (four datasets to fetch)
> Select -> Read 2 datasets
> Update -> Update 3rd dataset that is not yet fetched from the Select
> Transaction -> CommitRetaining
> Select -> Read next dataset
>
> Does select read the updated values for the 3rd dataset?
> It should, imho, since it's the context of the same transaction.
>
> And how does these kind of scenarious behave with inserts?
> I'm a bit puzzled as to how 'isolated' a select is.
>
> Regards,
> Daniel Albuschat
> --
> eat(this); // delicious suicide
>