John McGowan wrote:
> John McGowan wrote:
> > I looked into the various isolation levels
> when I
> > first discovered the problem I had, but
> didn't
> > know for sure if it would solve the problem
> that I
> > was having.
> >
> > I will try setting my server to use READ
> COMMITTED
> > instead of the default.
>
> Initial testing shows that this change was exactly
> what I needed.
>
> > In the meantime I have a question.
> >
> > If the app server opens up a connection and
> sets
> > autocommit to 0, Then uses it in a pool and
> lots
> > of various statements are sent to the server.
> Am
> > I missing something here, or is it true that
> if
> > there aren't any commit's done, all those
> > statements running the risk of being lost
> (rolled
> > back) if the connection is severed before it
> is
> > allowed to close down cleanly?
>
> I'm now guessing that the different isolation
> levels would have a differnt effect on how much
> data you would lose in a situation like this. I
> think I need to do some more reading on the
> subject before I know exactly what is going on.
John,
Not really, they only have an effect on what data the current transaction can 'see'. It has nothing to do with what data will get stored/saved.
If your appserver isn't committing at the end of a transaction, that's either a bug, or your application should be doing it (depending on whether you're using something like JTA/EJB or rolling your own persistence).
-Mark
Mark Matthews
Consulting Member Technical Staff - MySQL Enterprise Tools
Oracle
http://www.mysql.com/products/enterprise/monitor.html