Re: Transaction ISOLATION LEVEL - have I missed something?

On Thu, May 13, 2021 at 1:31 PM Pól Ua Laoínecháin <linehanp(at)tcd(dot)ie> wrote:

> I hope that clears up what I meant - and also that what I have written
> above demonstrates a reasonable understanding of the difference
> between the potential outcomes of an RC transaction and an S one?
>
>
It does. I see now you are trying to describe snapshots of data available
to statements in terms of database timestamps as opposed to referring to
transactional boundaries.

I've never seen isolation levels discussed in those terms before and do not
know whether it is accurate or missing some important nuances. With locks,
snapshots, and valid interleaving versus invalid interleaving (for
serializable) all coming into play the notion of timestamp isn't really in
scope. But if it helps for basic comprehension then it does have merit and
indeed the links you describe seem correct at first glance.

David J.