制定统计描述对象：

     /// <summary>

     /// 订单销售统计描述对象

     /// </summary>

     [TableMap("",TableType.View)]

     public class SumPrice:ITableView

     {

         public SumPrice()

         {

              //

              // TODO: 在此处添加构造函数逻辑

              //

         }

         #region ITableView 成员

         public Table GetTable()

         {

              // TODO:  添加 OrderV.GetTable 实现

              return DBMapping.Orders.INNER(DBMapping.Employees,DBMapping.Employees.EmployeeID)

                   &DBMapping.Orders.INNER(DBMapping.Customers,DBMapping.Customers.CustomerID)

                   & DBMapping.Orders.INNER(DBMapping.OrderDetails,DBMapping.Orders.OrderID);

         }

         private Double mPrice;

         [StatColumn("Quantity*UnitPrice*(1-Discount)",StatType.Sum)]

         public Double Price

         {

              get

              {

                   return mPrice;

              }

              set

              {

                   mPrice = value;

              }

         }

         #endregion

     }

     /// <summary>

     /// 按雇员分组销售统计描述对象

     /// </summary>