I realize that wasn't the question, but it does seem like a lot of
trouble to get the equivalent of setAutoCommit(true);
On 9/17/07, Robert DiFalco <rdifalco@stripped> wrote:
> Sure, but that wasn't really the question.
>
> -----Original Message-----
> From: Michael Dykman [mailto:mdykman@stripped]
> Sent: Monday, September 17, 2007 2:56 PM
> To: Robert DiFalco
> Cc: Baron Schwartz; mysql@stripped
> Subject: Re: Rollback on a Transaction with No Updates
>
> If your transaction are only 1 query deep, why use them at all? An
> individual query is already atomic, regardless of table type/server
> mode.
>
> - michael dkyman
>
>
> On 9/17/07, Robert DiFalco <rdifalco@stripped> wrote:
> > While it is functionally equivalent I wonder if it the code paths
> > taken are the same. I suppose for both commit and rollback mysql would
>
> > have to look for any pending work, if there were none both would do
> nothing.
> > That's what makes me think that there is probably no performance
> > difference between the two. I ask this because my programmers like to
> > do
> > this:
> >
> > con = ...
> > try
> > {
> > queryOnlyWith( con );
> > }
> > finally
> > {
> > con.rollback();
> > }
> >
> > And I wanted to make sure that this would perform the same and act the
>
> > same as issuing a commit (unless there was an exception but I'm not
> > analyzing that case).
> >
> > -----Original Message-----
> > From: Baron Schwartz [mailto:baron@stripped]
> > Sent: Monday, September 17, 2007 2:36 PM
> > To: Robert DiFalco
> > Cc: mysql@stripped
> > Subject: Re: Rollback on a Transaction with No Updates
> >
> > Robert DiFalco wrote:
> > > Is there any difference between calling rollback or commit on a
> > > transaction that did not alter data? For example, not a read-only
> > > transaction but a transaction that only performed read-only selects.
> > > Any difference in performance between calling rollback or commit? I
> > > know they are functionally the same at the high level.
> >
> > The only thing I could think of was possibly rollback would leave open
>
> > transaction and its read view if you are running in REPEATABLE READ
> > isolation mode, whereas commit begins a new transaction and discards
> > the read view. But I just tested that, and both commands start a new
> > transaction and discard the read view.
> >
> > That's a long way of saying they are functionally equivalent as far as
>
> > I know, as long as there are no changes to discard.
> >
> > Baron
> >
> >
> >
> > --
> > MySQL General Mailing List
> > For list archives: http://lists.mysql.com/mysql
> > To unsubscribe:
> http://lists.mysql.com/mysql?unsub=1
> >
> >
>
>
> --
> - michael dykman
> - mdykman@stripped
>
> - All models are wrong. Some models are useful.
>
>
>
--
- michael dykman
- mdykman@stripped
- All models are wrong. Some models are useful.
