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已答覆How to filter Include in ObjectQuery

  • 2009年5月7日 下午 08:13Dynamic 使用者勳章使用者勳章使用者勳章使用者勳章使用者勳章
     
    Background:
    ObjectQuery<Customer> myCollection = myEntityFrameworkContext.Customer.Include("Order.OrderDetail");

    (Each Customer has a collection of Order objects and each Order has a collection of OrderDetail objects)

    Question
    How can I filter the result or change the query in a way that only those resultsets are returned where OrderDetail with the productId = 2.

    something like this: myEntityFrameworkContext.Customer.Include("Order.OrderDetails").Where("it.Order.OrderDetail.productId = 2")

    Any help is much appreciated.

解答

  • 2009年5月8日 上午 09:10Dynamic 使用者勳章使用者勳章使用者勳章使用者勳章使用者勳章
     已答覆
    I found the solution myself :)

    myEntityFrameworkContext.Customer.Include("Order.OrderDetails").Where(customer => customer.Order.Any(order => order.OrderDetail.Any(orderDetail => orderDetail.ProductId ==2)));
    • 已標示為解答Dynamic 2009年5月8日 上午 09:10
    •  
  • 2009年7月4日 下午 08:31Dynamic 使用者勳章使用者勳章使用者勳章使用者勳章使用者勳章
     已答覆
    I think this is a bug with the Entity Framework or I don't know how to do it.

    Anyway, the only way I found is to change the Object Query direction.

    The "many" side of the relationship must come first always:

    myEntityFrameworkContext.OrderDetail.Include("Order.Customer").Where(orderDetail.ProductId ==2);

    Now only the Order and Customer are returned which are associated with the selected OrderDetail.

    Now again I have to Convert the data to the format I need which means Customer.Order.OrderDetail not OrderDetail.Order.Customer
    • 已編輯Dynamic 2009年7月4日 下午 08:43
    • 已標示為解答Dynamic 2009年7月4日 下午 08:31
    •  

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  • 2009年5月8日 上午 09:10Dynamic 使用者勳章使用者勳章使用者勳章使用者勳章使用者勳章
     已答覆
    I found the solution myself :)

    myEntityFrameworkContext.Customer.Include("Order.OrderDetails").Where(customer => customer.Order.Any(order => order.OrderDetail.Any(orderDetail => orderDetail.ProductId ==2)));
    • 已標示為解答Dynamic 2009年5月8日 上午 09:10
    •  
  • 2009年7月3日 下午 04:38Dynamic 使用者勳章使用者勳章使用者勳章使用者勳章使用者勳章
     

    Well, I just noticed a problem with this.

    Customer is filtered but other tables are returned entirely! (not filtered)

    Any idea?

  • 2009年7月4日 下午 08:31Dynamic 使用者勳章使用者勳章使用者勳章使用者勳章使用者勳章
     已答覆
    I think this is a bug with the Entity Framework or I don't know how to do it.

    Anyway, the only way I found is to change the Object Query direction.

    The "many" side of the relationship must come first always:

    myEntityFrameworkContext.OrderDetail.Include("Order.Customer").Where(orderDetail.ProductId ==2);

    Now only the Order and Customer are returned which are associated with the selected OrderDetail.

    Now again I have to Convert the data to the format I need which means Customer.Order.OrderDetail not OrderDetail.Order.Customer
    • 已編輯Dynamic 2009年7月4日 下午 08:43
    • 已標示為解答Dynamic 2009年7月4日 下午 08:31
    •