ConnectionStringSettings settings = ConfigurationManager.ConnectionStrings["DB"];

            DbProviderFactory provider = DbProviderFactories.GetFactory(settings.ProviderName);

            using (DbConnection conn = provider.CreateConnection())
            {
                conn.ConnectionString = settings.ConnectionString;
                conn.Open();
                DbCommand cmd = conn.CreateCommand();

                cmd.CommandText = "Select top 10 * From ShortTermBill";

                DbDataAdapter da = provider.CreateDataAdapter();

                da.SelectCommand = cmd;

                DataSet ds = new DataSet();

                da.Fill(ds);

                da.Dispose();

                Console.WriteLine(ds.Tables[0].Rows[0]["BillCode"]);
            }