Don't know if you ever solved this but I just watched a developer run into the problem. It occured because the table he was deleting had a foreign key constraint to another table.

Switching the order in which the objects were deleting (there were several) resolved the issue by removing the data in a way that didn't violate the constraint.


>>I have a very simple Business object that reads, write,delete and selects from a single table. When I try to delete a record I get
>>Concurrency violation: the DeleteCommand affected 0 of the expected 1 records.
>
>Can you describe what your form is doing? It seems unusual to get a concurrency violation when deleting. It looks like you are using an mmButtonDelete instance on your form. Have you specified a primary business object on your form or have you set the button's BindingSource property?
>
>
>The form adds, updates and delete data from a single table, it has two primary keys. I am using the base delete button. I have specified a primary business object.
>
>Public Sub New()
> Me.oSponsor = CType(Me.RegisterPrimaryBizObj(New Sponsor()), Sponsor)
> Me.oSponsor.DatabaseKey = "FRONTOFFICE"
> ' This call is required by the Windows Form Designer.
> InitializeComponent()
> Me.grdSponsor.AutoGenerateColumns = False
> ' Retrieve all employees
> Me.oSponsor.GetAllData()
> ' Specify the Navigation control
> Me.NavControl = Me.grdSponsor
> End Sub
>
>
>This the message I am getting
>
>Concurrency violation: the DeleteCommand affected 0 of the expected 1 records.
>
>Below is the stack trace
>
>at System.Data.Common.DbDataAdapter.UpdatedRowStatusErrors(RowUpdatedEventArgs rowUpdatedEvent, BatchCommandInfo[] batchCommands, Int32 commandCount)
> at System.Data.Common.DbDataAdapter.UpdatedRowStatus(RowUpdatedEventArgs rowUpdatedEvent, BatchCommandInfo[] batchCommands, Int32 commandCount)
> at System.Data.Common.DbDataAdapter.Update(DataRow[] dataRows, DataTableMapping tableMapping)
> at System.Data.Common.DbDataAdapter.UpdateFromDataTable(DataTable dataTable, DataTableMapping tableMapping)
> at System.Data.Common.DbDataAdapter.Update(DataSet dataSet, String srcTable)
> at OakLeaf.MM.Main.Data.mmDataAccessSql.SaveDataSet(DataSet ds, String tableName, String primaryKeyName, Boolean retrieveAutoIncrementPK, IDbDataAdapter dbAdapter)
> at OakLeaf.MM.Main.Business.mmBusinessObject.Delete(DataRow dr)
> at OakLeaf.MM.Main.Business.mmBusinessObject.Delete(DataRowView drView)
> at OakLeaf.MM.Main.Windows.Forms.mmBusinessForm.Delete(mmBusinessObject bizObj, DataRowView drView)
> at OakLeaf.MM.Main.Windows.Forms.mmBusinessForm.Delete(mmBusinessObject bizObj, String tableName)
> at OakLeaf.MM.Main.Windows.Forms.mmButtonHelper.DeleteHandler(Object button, String bindingSource, String bindingSourceMember, mmBaseBusinessObject& bizObj)
> at OakLeaf.MM.Main.Windows.Forms.mmButtonDelete.mmButtonDelete_Click(Object sender, EventArgs e)
> at System.Windows.Forms.Control.OnClick(EventArgs e)
> at System.Windows.Forms.Button.OnClick(EventArgs e)
> at System.Windows.Forms.Button.WndProc(Message& m)
> at System.Windows.Forms.Control.ControlNativeWindow.OnMessage(Message& m)
> at System.Windows.Forms.Control.ControlNativeWindow.WndProc(Message& m)
> at System.Windows.Forms.NativeWindow.DebuggableCallback(IntPtr hWnd, Int32 msg, IntPtr wparam, IntPtr lparam)
> at System.Windows.Forms.UnsafeNativeMethods.SendMessage(HandleRef hWnd, Int32 msg, IntPtr wParam, IntPtr lParam)
> at System.Windows.Forms.Control.SendMessage(Int32 msg, IntPtr wparam, IntPtr lparam)
> at System.Windows.Forms.Control.ReflectMessageInternal(IntPtr hWnd, Message& m)
> at System.Windows.Forms.Control.WmCommand(Message& m)
> at System.Windows.Forms.Control.WndProc(Message& m)
> at System.Windows.Forms.ScrollableControl.WndProc(Message& m)
> at System.Windows.Forms.Control.ControlNativeWindow.OnMessage(Message& m)
> at System.Windows.Forms.Control.ControlNativeWindow.WndProc(Message& m)
> at System.Windows.Forms.NativeWindow.DebuggableCallback(IntPtr hWnd, Int32 msg, IntPtr wparam, IntPtr lparam)
> at System.Windows.Forms.UnsafeNativeMethods.CallWindowProc(IntPtr wndProc, IntPtr hWnd, Int32 msg, IntPtr wParam, IntPtr lParam)
> at System.Windows.Forms.NativeWindow.DefWndProc(Message& m)
> at System.Windows.Forms.Control.DefWndProc(Message& m)
> at System.Windows.Forms.Control.WmMouseUp(Message& m, MouseButtons button, Int32 clicks)
> at System.Windows.Forms.Control.WndProc(Message& m)
> at System.Windows.Forms.ButtonBase.WndProc(Message& m)
> at System.Windows.Forms.Button.WndProc(Message& m)
> at System.Windows.Forms.Control.ControlNativeWindow.OnMessage(Message& m)
> at System.Windows.Forms.Control.ControlNativeWindow.WndProc(Message& m)
> at System.Windows.Forms.NativeWindow.DebuggableCallback(IntPtr hWnd, Int32 msg, IntPtr wparam, IntPtr lparam)
> at System.Windows.Forms.UnsafeNativeMethods.DispatchMessageW(MSG& msg)
> at System.Windows.Forms.Application.ComponentManager.System.Windows.Forms.UnsafeNativeMethods.IMsoComponentManager.FPushMessageLoop(Int32 dwComponentID, Int32 reason, Int32 pvLoopData)
> at System.Windows.Forms.Application.ThreadContext.RunMessageLoopInner(Int32 reason, ApplicationContext context)
> at System.Windows.Forms.Application.ThreadContext.RunMessageLoop(Int32 reason, ApplicationContext context)
> at System.Windows.Forms.Application.Run(Form mainForm)
> at ACELO.OSP.WINDOW.AppMainEntry.Main() in C:\OSP\Acelo.OSP.Window\Acelo.OSP.Window\Main.vb:line 52