This example uses the EntitySpaces esTransactionScope class to save two EntitySpaces objects in a transaction. The esTransactionScope is used just like the .NET TransactionScope class only it is not distributed and works at the connection level.

Employees emp = new Employees (); 
emp.FirstName = "Mike"; 
emp.LastName = "Entity"; 

using(esTransactionScope scope = new esTransactionScope()) 
{ 
    emp.Save(); 

    Dependent dep = new Dependent (); 
    dep.EmployeeID = emp.EmployeeID; 
    dep.FirstName = "Jr"; 
    dep.LastName = "Entity"; 
    dep.Save(); 
}

Of course, when you call Save and are using our Hierarchical Model then you don't have to explicitly create a transaction. The only time you should ever declare a transaction is when you need to save two objects that are unrelated or not in the hierarchical model. 

I am using ES and VistaDB to do an Hierarchical save.  According to the forum - http://www.vistadb.net/forums/viewtopic.php?t=1285&highlight=transaction - Vista requires you to manually rollback a transaction.  It seems that these transactions are getting 'stuck' when I break out of the debugger during the save.  I am getting a concurency error - see below.

 Here is my code to save the item back to the DB:

                //save the employee to the local DB
                    employee.EndEdit();

                    if (employee.Collection != null)
                    {
                        employee.Collection.Save();
                    }
                    else
                    {
                        employee.Save();
                    }

and here is the error I am getting:

1    VistaDB.Diagnostic.VistaDBException was unhandled
2      Message="\r\nError 455: Concurrency error. The row is being updated or deleted by another active transaction \r\nError 251: Cannot update row:  \nTable: 'Employee', RowId = 170\n\r\n"
3      Source="EntitySpaces.Core"
4      ErrorId=251
5      LevelMessage="Error 251: Cannot update row:  \nTable: 'Employee', RowId = 170"
6      StackTrace:
7           at EntitySpaces.Core.esEntityCollection.SaveToProviderInsertsUpdates(esSqlAccessType sqlAccessType)
8           at EntitySpaces.Core.esEntityCollection.SaveToProvider(esSqlAccessType sqlAccessType)
9           at EntitySpaces.Core.esEntityCollection.Save(esSqlAccessType sqlAccessType)
10          at EntitySpaces.Core.esEntityCollection.Save()
11          at rhi.EmployeeEntry.EmployeeManagement.AddEditEmployeeViewPresenter.OnSubmitEmployee_Click() in C:\Projects\EmployeeEntry.root\!EmployeeEntryClient\Source\EmployeeManagement\EmployeeManagement.Module\Views\AddEditEmployeeViewPresenter.cs:line 398
12          at rhi.EmployeeEntry.EmployeeManagement.AddEditEmployeeView.btnSaveAndSubmit_Click(Object sender, EventArgs e) in C:\Projects\EmployeeEntry.root\!EmployeeEntryClient\Source\EmployeeManagement\EmployeeManagement.Module\Views\AddEditEmployeeView.cs:line 142
13          at System.Windows.Forms.Control.OnClick(EventArgs e)
14          at System.Windows.Forms.Button.OnClick(EventArgs e)
15          at System.Windows.Forms.Button.OnMouseUp(MouseEventArgs mevent)
16          at System.Windows.Forms.Control.WmMouseUp(Message& m, MouseButtons button, Int32 clicks)
17          at System.Windows.Forms.Control.WndProc(Message& m)
18          at System.Windows.Forms.ButtonBase.WndProc(Message& m)
19          at System.Windows.Forms.Button.WndProc(Message& m)
20          at System.Windows.Forms.Control.ControlNativeWindow.OnMessage(Message& m)
21          at System.Windows.Forms.Control.ControlNativeWindow.WndProc(Message& m)
22          at System.Windows.Forms.NativeWindow.DebuggableCallback(IntPtr hWnd, Int32 msg, IntPtr wparam, IntPtr lparam)
23          at System.Windows.Forms.UnsafeNativeMethods.DispatchMessageW(MSG& msg)
24          at System.Windows.Forms.Application.ComponentManager.System.Windows.Forms.UnsafeNativeMethods.IMsoComponentManager.FPushMessageLoop(Int32 dwComponentID, Int32 reason, Int32 pvLoopData)
25          at System.Windows.Forms.Application.ThreadContext.RunMessageLoopInner(Int32 reason, ApplicationContext context)
26          at System.Windows.Forms.Application.ThreadContext.RunMessageLoop(Int32 reason, ApplicationContext context)
27          at System.Windows.Forms.Application.Run(Form mainForm)
28          at Microsoft.Practices.CompositeUI.WinForms.FormShellApplication`2.Start()
29          at Microsoft.Practices.CompositeUI.CabApplication`1.Run()
30          at rhi.EmployeeEntry.Infrastructure.Shell.ShellApplication.RunInDebugMode() in C:\Projects\EmployeeEntry.root\!EmployeeEntryClient\Source\Infrastructure\Shell\ShellApplication.cs:line 56
31          at rhi.EmployeeEntry.Infrastructure.Shell.ShellApplication.Main() in C:\Projects\EmployeeEntry.root\!EmployeeEntryClient\Source\Infrastructure\Shell\ShellApplication.cs:line 47
32          at System.AppDomain.nExecuteAssembly(Assembly assembly, String[] args)
33          at System.AppDomain.ExecuteAssembly(String assemblyFile, Evidence assemblySecurity, String[] args)
34          at Microsoft.VisualStudio.HostingProcess.HostProc.RunUsersAssembly()
35          at System.Threading.ThreadHelper.ThreadStart_Context(Object state)
36          at System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state)
37          at System.Threading.ThreadHelper.ThreadStart()
38   

EntitySpaces always does a rollback or commit, that is why we use the "using" syntax, my guess is that the debugger is just "killing" the process or something. Also, we have found no bugs in ES relating to VistaDB, however, we have found many bugs in VistaDB. That is not to say we do not like VistaDB, I think it has great potential and is far superior to SQL CE by a mile.

That being said, do you have Timestamp columns in your tables, that is the only way I can see you getting a concurrency error?  I tend to stop my application rather than press "Stop  Debugging" in Visual Studio for this very reason.

If this only happens when you stop the debugger I can see where this might be annoying but don't really think this is an EntitySpaces "thing" ? However, we are here to help.
 

No there are no timestamp columns in my tables.  Is there ANY way to figure out exactly what 'command' is throwing the Vista DB error.  I need someway to see the exact query that's being passed in to vista.  There doesn't seem to be anything similar to SQL Query Analyzer or process monitor, etc. like SQL 2005 has.

Any help would be greatly appreciated - this is driving me crazy!

No, it occurs whether I stop the debugger or not.  It also occurs in the runtime.
How would I know if I am using connection pooling - where is that setting?

Here is the entier 'SAVE' method which occurs when the SAVE AND SUBMIT button is clicked.  Other than that, I basically have a three-part tab page; each with employee details on it.  I have a related child table called "EmployeeStatusChange" which keeps up with the 'status' of each employee (hired, fired, loa, etc).  Basically, I am trying to add a new record to this table each time.  I can give you some of that code, if it is helpful.

1    internal void OnSubmitEmployee_Click()
2            {
3                //validate entire form before allowing the save
4                if (_employeeDetailView.ValidateForSave(false) && _employeeJobcodeView.ValidateForSave() && _employeeZapView.ValidateForSave())
5                {
6                    //set the employee's status, if not set, or if status is DRAFT or RECOVERED
7                    if (employee.EmployeeStatusID == null || employee.EmployeeStatusID == EmployeeStatus.DRAFT || employee.EmployeeStatusID == EmployeeStatus.RECOVERED)
8                        employee.EmployeeStatusID = EmployeeStatus.ACTIVE;
9    
10                   //set the employee's primary jobcode, if available
11                   if (employee.EmployeeJobCodeCollectionByEmployeeID.Count > 0)
12                       employee.PrimaryJobCodeID = ((EmployeeJobCode)employee.EmployeeJobCodeCollectionByEmployeeID[0]).JobCodeAloha;
13   
14                   //set the create and/or updated time
15                   employee.CreatedDate = employee.CreatedDate ?? DateTime.Now;
16                   employee.LastModifiedDate = DateTime.Now;
17   
18                   //set the employee's hire date, if not already set
19                   employee.HireDate = employee.HireDate ?? employee.AlohaStartDate;
20   
21                   //save the employee to the local DB
22                   employee.EndEdit();
23   
24                   if (employee.Collection != null)
25                   {
26                       employee.Collection.Save();
27                   }
28                   else
29                   {
30                       employee.Save();
31                   }
32   
33                   string msg = string.Empty;
34                   msg += "Saving employee to local database ... successful.\n";
35                    msg += "Employee " + employee.ToString() + " has been created.";
36                   this.shellNotificationService.Show(msg, "Creating New Employee");
37   
38                   //close the view
39                   this.OnCloseView();
40               }
41   
42           }

Yes, but it wasn't very helpful.  Acutally, I solved the problem by reviewing my LastEmployeeStatusChange property of my Employee object.  What was happening, is that I was adding a new object (employee.statusChangeCollection.AddNew()) if one didn't exist.  The problem is that no properties were being set on that object, so it was throwing errors when trying to write to the database.  To solve this, I implemented a function that only added the 'statusChange' object to the collection if and when the variables were set.  This seemed to fix the problem - I hope it really did! 

            //add the LastEmployeeStatusChange to the EmployeeStatusChangeCollectionByEmployeeID, if needed
            if (employee.LastEmployeeStatusChange.EmployeeID == null)
            {
                employee.LastEmployeeStatusChange = employee.EmployeeStatusChangeCollectionByEmployeeID.AddNew();
                chkIsTerminated.Enabled = false;
                bool holdChecked = chkIsTerminated.Checked;

               //call setLookupBindingDatasources() to rebind the "LastEmployeeStatusChange" object
                setLookupBindingDatasources();
                chkIsTerminated.Enabled = true;
                chkIsTerminated.Checked = holdChecked;
                return;
            }