Re: UpdateableResultSets and concurrency.

On Sun, 8 Jul 2001, Ola Sundell wrote:

> On Tue, 26 Jun 2001, Dave Cramer wrote:
>
> > Ola,
> >
> > How are you planning on determining if the underlying data has been
> > changed by some other process? There is a system column called xmin
> > which can be used, however you will have to add it to the select.
> >
> > Dave
>
> At first, I will let the backend handle any and all problems that might
> occur. I will simply forward any exceptions I get, and let the overlying
> code handle the problems. I checked the MySQL driver, and that is how they
> are doing it.
>
> I wonder how it works with non-free databases. Does anyone here know?

Silly me.

When I woke up this morning, I realised that MySQL doesn't support
transactions. I re-read the JDBC spec, and I will do a simple optimistic
concurrency control by starting a transaction, re-reading the row and
checking the values.

mvh Ola

--
Ola Sundell
ola@miranda.org - olas@wiw.org - ola.sundell@upright.se
http://miranda.org/~ola