write something to database in nop 2.0?

hi.
somewhere in my payment module I need to write something to database.
but I'm not familiar with entity framework.
is there any problem with using the old fashioned ado.net?
and how can I use entity framework to accomplish a data insert into database?

Sometimes I need run a query without EF, here is what I do:

                var dataSettingsManager = new DataSettingsManager();
                var dataProviderSettings = dataSettingsManager.LoadSettings();

                using (SqlConnection connection = new SqlConnection(dataProviderSettings.DataConnectionString))
                {
                        SqlCommand cmd = new SqlCommand("UPDATE [dbo].[NOrder] SET [ExportedOnUtc] = GETUTCDATE() WHERE OrderID = @OrderID", connection);
                        cmd.Parameters.Add(new System.Data.SqlClient.SqlParameter { ParameterName = "OrderID", Value = order.Id });
                        connection.Open();
                        cmd.ExecuteNonQuery();
                }

I don't know if there is a simpliest way to get connexionString...