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When saving a list to the database I have the following code: 

Using Trans As TransactionManager = DataRepository.Provider.CreateTransaction()
   Trans.BeginTransaction()               ' begin a transaction
   Try
      Save(Trans, List)                   ' save the changed records
      Trans.Commit()                      ' commit the transaction and accept changes

   Catch ex As Exception
      Trans.Rollback()                    ' rollback the transaction
      ExceptionPolicy.HandleException

   End Try
End Using

If there is a problem during the save and an exception is thrown I know that the records to the
database will be rolled back but how do I revert the list back
to it's original state since NetTiers has already done the AcceptChanges?

Hello,
There are two things you can do in this situation. The first situation one would do if they want to keep the list contents, but not the actions performed on it, and the second is get the list before all the additions to it were made.
1.    Create a copy of the list before beginning the transaction. If the transaction fails then set the list back to the copy of the list.
2.    Call into the data provider again (with caching off) and get the initial list back before the modifications were made.

Thanks

-Blake Niemyjski

Thank you very much.

Interesting thread.  At first I didn't understand what you problem is and now I think I get it.  Tell me if I am wrong.

You have a TList of items you are saving.  If halfway through there is an error, all the previously successful saves from the List have been Accepted.  Well, interesting find.  I think this needs to be on a ToDo list.  I think we should look at fixing this.  It's not a trivial change, but in my code I would want this to work right.  Suprised I haven't come accross this yet.

jeff

 You are correct. I think it would be cool if we could add transaction support to an (TList) object.  I'm pretty sure someone has already done this at the code project as I remember reading about this somewhere. It might be pretty difficult to do...

Thanks

-Blake

I think that maybe it should be changed to allow the program to AcceptChanges after the transaction.commit.  Accept changes would also have to do things like delete the DeletedItems list etc.