> I built a class called Database wich encapsulates a JBird
> Connection. When I call database.connect(), it is created an
> auto-committed Connection. The method used for updates is called
> execUpdate and is synchorinzed. So, I create an Database object,
> call the method connect and start the threads. Each thread will then
> call the execUpdate method.

Sounds good to me.

> I made a step-by-step execution and the output of executeUpdate is 1
> just as you said. The connection is auto-committed, as I said
> before. Do you know if an auto-committed transaction can be rolled
> back? If yes, is there any way of discovering if it occurred and
> why?

No, you should get exception then. If server says that it was
committed, then it was committed. Check if no exception is ignored.

Roman