Re: Documenting serializable vs snapshot isolation levels

> The effects are different, I think, in that there isn't a
> serialization failure in some conflict cases where you would get one
> with actual updates.  I found a paper on how to use updates to provide
> serializable transactions in a snapshot database, and I'd have to
> review closely to see how that difference affected the technique.  I
> had been thinking that the WAL generation and bloat issues made the
> technique pretty iffy, but if SELECT FOR UPDATE suffices in place of
> most of the proposed updates, it just might be feasible.

In fact, I think SELECT FOR SHARE is enough.  That will give you
better concurrency, since it will block only updates and not
concurrent read transactions.

...Robert