Distributed transactions are transactions that can span multiple resource managers, such as SQL Server and Oracle, and reconcile transactions among them.

iBATIS.NET introduces a new TransactionScope class mimicking the new TransactionScope found in the System.Transactions namespace (.NET Framework 2.0). This class supports MSMQ, ADO.NET, SqlServer, and DTC transaction models. This is a simple managed interface to COM+'s SWC (Services Without Components) Transactions. It can be used only by developers using .NET 1.1 and Windows XP SP2 or Windows Server 2003 since it implements distributed transactional support using the ServiceDomain class.

Usage is simple, as seen in the following example where a code block is made transactional à la Indigo (moving to Indigo will be easier since it is the same API):

[C#]
using IBatisNet.Common.Transaction;

using (TransactionScope tx = new TransactionScope())
{
   daoManager.OpenConnection();
   // Transaction will be automatically associated with it
   account = accountDao.GetAccountById(1001);
   account.FirstName = "Gilles";
   accountDao.Update(account);
   daoManager.CloseConnection();

   daoManager2.OpenConnection();
   // Transaction will be automatically associated with it
   joeCool = userDao.Load("joe_cool");
   joeCool.LastLogon = stamp;
   daoManager2.CloseConnection();

   tx.Complete(); // Commit
}

It is important to make sure that each instance of this class gets Close()'d. The easiest way to ensure that each instance is closed is with the using statement in C#. When using calls Dispose on the transaction scope at the end of the using code block, the ambient transaction will be commited only if the Complete() method has been called.

	Note
	This class does not support a nested transaction scope with different transaction options.

The next section provides some tips on how to write a DAO like the AccountDao shown in the previous example.