Q:

TransactionScope disposal failure

I'm using the TransactionScope class within a project based on Silverlight and RIA services. Each time I need to save some data, I create a TransactionScope object, save my data using Oracle ODP, then call the Complete method on my TransactionScope object and dispose the object itself:
public override bool Submit(ChangeSet changeSet)
    {
        TransactionOptions txopt = new TransactionOptions();
        txopt.IsolationLevel = IsolationLevel.ReadCommitted;
        using (TransactionScope tx = new TransactionScope(TransactionScopeOption.Required, txopt))
        {
            // Here I open an Oracle connection and fetch some data
            GetSomeData();

            // This is where I persist my data
            result = base.Submit(changeSet);

            tx.Complete();
        }

        return result;
    }

My problem is, the first time I get the Submit method to be called, everything is fine, but if I call it a second time, the execution gets stuck for a couple of minutes after the call to Complete (so, when disposing tx), then I get the Oracle error "ORA-12154". Of course, I already checked that my persistence code completes without errors. Any ideas?
Edit: today I repeated the test and for some reason I'm getting a different error instead of the Oracle exception:
System.InvalidOperationException: Operation is not valid due to the current state of the object.
at System.Transactions.TransactionState.ChangeStatePromotedAborted(InternalTransaction tx)
at System.Transactions.InternalTransaction.DistributedTransactionOutcome(InternalTransaction tx, TransactionStatus status)
at System.Transactions.Oletx.RealOletxTransaction.FireOutcome(TransactionStatus statusArg)
at System.Transactions.Oletx.OutcomeEnlistment.InvokeOutcomeFunction(TransactionStatus status)
at System.Transactions.Oletx.OletxTransactionManager.ShimNotificationCallback(Object state, Boolean timeout)
at System.Threading._ThreadPoolWaitOrTimerCallback.PerformWaitOrTimerCallback(Object state, Boolean timedOut)

A:

I somehow managed to solve this problem, although I still can't figure out the reason it showed up in the first place: I just moved the call to GetSomeData outside the scope of the distributed transaction. Since the call to Submit may open many connections and perform any kind of operations on the DB, I just can't tell why GetSomeData was causing this problem (it just opens a connection, calls a very simple stored function and returns a boolean). I can only guess that has something to do with the implementation of the Submit method and/or with the instantiation of multiple oracle connections within the same transaction scope.

