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[Allen Shaw]

tedd wrote:
> Oh, and there's a part 2 as well.
>
> http://www.devshed.com/c/a/MySQL/Using-Transactions-In-MySQL-Part-2
Hi Tedd,

If I understand the intro correctly, that article is about standard 
mysql transactions, but the problem I'm having won't really be solved 
with usual START TRANSACTION / COMMIT transactions.  As an analogy, 
consider a instant messenger session between two people on very slow 
connections.  Transactions can make sure that when one types a message, 
that message arrives to its recipient intact -- the sentence is not 
broken up or mangled.  The latency problem, though, is when these two 
people are sending consecutive messages to each other but not receiving 
responses in real time.  It becomes vaudeville very quickly: (Are you 
coming?  Will you be late? Yes. Oh,  I mean no.  Well I meant that other 
question.  Whatever.) 

The problem here is that the user's actions are dependent on the live 
data, and the live data can be changed by multiple users at once, with 
the various users remaining some minutes (or possibly more) behind the 
actual live data.  It's a problem that we already have to guard against 
in a multi-user environment, but the latency period, and the potential 
for collisions, is hugely increased. 

Looks like I have some coding to do.

-- 
Allen Shaw
slidePresenter (http://slides.sourceforge.net)