Public Function addTable(SQL As String, TableName As String) As DataTable
        da.SelectCommand = New OleDbCommand(SQL)
        da.SelectCommand.Connection = conn
 
        Try
            da.Fill(ds, TableName)
            Return ds.Tables(TableName))
        Catch ex As Exception
            MsgBox(ex.Message)
            Return Nothing
        End Try
End Function

Public Sub SendChangesToDatabase()
        da.Fill(_dt)
        Dim objCommandBuilder As New OleDbCommandBuilder(da)
        da.Update(ds, _dt.TableName)
End Sub