Thanks Kathy. I will do some reading on this. -----Original Message----- From: Kathey Marsden [mailto:kmarsdende...@sbcglobal.net] Sent: Tuesday, August 23, 2011 9:19 AM To: derby-dev@db.apache.org Cc: Bergquist, Brett Subject: Re: Have a database that has a phantom "transaction" even after booting the database clean in embedded mode
On 8/23/2011 5:21 AM, Bergquist, Brett wrote: > I guess I was under the assumption that it would go away if I booted the > database clean. It seems to me that a database that has been stopped and > booted clean would invalidate an existing transactions and clean them up. Is > this not the case with XA transactions? > In A two phase commit XA transaction, if there is a crash between the prepare and the final commit or rollback, there is not a way for Derby to know whether the overall distributed transaction was committed or rolled back, so even after the database is rebooted, the transaction remains in the prepared state and has to be manually recovered and appropriately committed or rolled back to match the global transaction. The prepare just guarantees that either commit or rollback will work. The JTA spec which provides the Java interfaces for XA transactions is based on the open group XA Specification, which is a good resource for understanding XA concepts. https://www2.opengroup.org/ogsys/jsp/publications/PublicationDetails.jsp?catalogno=c193 HTH Kathey PS. There is a single phase commitin XAResource.commit(Xid xid, boolean onePhase) if your transaction involves just a single database and that is all you require, but I don't know if you have overall handling of the XA transaction processing.
