SqlConnection cn = new SqlConnection(NWindConnectionString);
SqlCommand cmd = new SqlCommand("SELECT c.CustomerID, c.CompanyName, " +
"c.ContactName, o.OrderID, o.OrderDate FROM Customers AS c INNER JOIN " +
"Orders AS o ON c.CustomerID = o.CustomerID", cn );

using (cn) {
cn.Open();

using (SqlDataReader dr = cmd.ExecuteReader(
CommandBehavior.CloseConnection)) {
gridCustomersOrders.DataSource = dr;
gridCustomersOrders.DataBind();
}
}
