self-tracking-entities | 易学教程

Self Tracking Entities - AcceptChanges cannot continue because the object's key values conflict with another object in the ObjectStateManager

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问题 I've been stuck with this problem for over a week now. Hopefully some one can point me in the right direction. I start with a brief description of my schema. Asset 1--->1 Address *-->1 Area *-->1 Region *-->1 Country Package 1-->* Asset Using Self Tracking Entity (STE) + WCF. Steps: Call data store for a list of assets. Call data store for a list of packages. User selects a package and assign some assets to it. Save package. In step 2, the call uses eager loading of Addresses. from p in

Entity Framework Split Table Delete

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问题 I'm using EF 4 STE's to model an Attachment object. The Attachment contains a Name, Description, Date, and most importantly Data ( byte[] ). To optimize loading, I don't want to retrieve the Data property until it's absolutely necessary, i.e. when the user clicks Download from the client. In an effort to follow this approach, I used the table-splitting technique described here. I split my Attachment table up into Attachment (Name, Description, Date) and AttachmentData (Data). It's a 1-to-1

Is it recommended to use Self Tracking Entities with WCF services?

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I want to know if using Self Tacking Entities (in Entity Framework) is recommended with WCF services? If yes, then can you guide me to a tutorial which may guide how to do that? Actually, I am going to develop a WPF application using Prism with MEF and MVVM. I have decided to use Entity Framework. I want suggestions and advices regarding this approach. Any help will be appreciated. Ladislav Mrnka I want to know if using Self Tacking Entities (in Entity Framework) is recommended with WCF services? It depends who you ask. If you ask MS they will tell you Yes because they simply don't have

Preventing StackOverflowException while serializing Entity Framework object graph into Json

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问题 I want to serialize an Entity Framework Self-Tracking Entities full object graph (parent + children in one to many relationships) into Json. For serializing I use ServiceStack.JsonSerializer . This is how my database looks like (for simplicity, I dropped all irrelevant fields): I fetch a full profile graph in this way: public Profile GetUserProfile(Guid userID) { using (var db = new AcmeEntities()) { return db.Profiles.Include("ProfileImages").Single(p => p.UserId == userId); } } The problem

Is it recommended to use Self Tracking Entities with WCF services?

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问题 I want to know if using Self Tacking Entities (in Entity Framework) is recommended with WCF services? If yes, then can you guide me to a tutorial which may guide how to do that? Actually, I am going to develop a WPF application using Prism with MEF and MVVM. I have decided to use Entity Framework. I want suggestions and advices regarding this approach. Any help will be appreciated. 回答1: I want to know if using Self Tacking Entities (in Entity Framework) is recommended with WCF services? It

What is the purpose of self tracking entities?

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问题 I\'ve been reading about self-tracking entities in .net and how they can be generated from a *.edmx file. The thing that I\'m struggling to understand is what generating these entities gives you over the basic EF entities? Also, some people have mentioned self tracking entities and Silverlight, but why would you use these rather than the client side or shared classes generated by RIA services? What is the point of self-tracking entities and why would you use them? 回答1: Self tracking entities

Self Tracking Entities vs POCO Entities

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问题 We are starting a new web based product in which we are planning to expose our business logic through WCF services. We will be using ASP.NET 4.0, C#, EF 4.0. In future we want to build iphone applications and WPF applications based on the services. I have been reading a lot about using POCO vs Self Tracking Entities (STE) and from my understand the STEs do not work well with the web scenario. Can anyone shed more light on this issue? 回答1: For me STE is absolutely wrong concept. It is just

What is the purpose of self tracking entities?

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I've been reading about self-tracking entities in .net and how they can be generated from a *.edmx file. The thing that I'm struggling to understand is what generating these entities gives you over the basic EF entities? Also, some people have mentioned self tracking entities and Silverlight, but why would you use these rather than the client side or shared classes generated by RIA services? What is the point of self-tracking entities and why would you use them? Ladislav Mrnka Self tracking entities (STE) are implementation of change set (previous .NET implementation of change set is DataSet )