entity-framework-4.1

I am getting the following error when my application runs: System.InvalidOperationException: The type 'ContactModels+Contact' was not mapped. Check that the type has not been explicitly excluded by using the Ignore method or NotMappedAttribute data annotation. Verify that the type was defined as a class, is not primitive, nested or generic, and does not inherit from EntityObject. It is failing when my DBContext class tries to initialize the entities: public class DB : DbContext { public DbSet<ContactModels.Contact> Contacts { get; set; } .... } The Contact model is as follows: public class

I have a set of entities that I have queried from IDbSet in my DbContext. I now want to iterate over each entity and query their child collections, which are defined in the entity as ICollection. Is it correct to call AsQueryable() on the child collections and run my linq query on that? If so, will my queries be linq-to-objects or does the collection object populated by EF implement IQueryable that goes to the database? Thanks for any insight on this. Ladislav Mrnka It whole depends on how your entities are defined and if lazy loading is enabled. Your query to IDbSet will be linq-to-entities.

Issue: Child model collection in MVC3 & Entity Framework 4.1 is being updated properly in model via Edit action but the values are not being saved in DB. Overview: - Model object Person contains object CaseRef's - Person property updates are getting saved in the DB on db.SaveChanges() but internal collection CaseRef property updates are not being saved - All values are bound/mapped correctly upon entry of HttpPost ActionResult Edit() so the model is being updated successfully from Form submit (Edit View). Models: public class Person { public Person() { this.CaseRefs = new HashSet<CaseRef>(); }

I'm building a forum project for ASP.NET MVC 3, running on .NET 4 with the latest version of Entity Framework. I have the usual forum design, with a Board with Categories, and Categories with Forums, Forums with Topics and Topics with Posts etc. Simplified: public class Category { [Required] public virtual Board Board { get; set; } } public class Forum { [Required] public virtual Category Category { get; set; } } public class Topic { [Required] public virtual Forum Forum { get; set; } } public class Post { [Required] public virtual Topic Topic { get; set; } } When a new post is created the

recently I learned Entity Framework by Pro Entity Framework 4.0 book... Now,I want to write the project by EF ...With these conditionsو which way is better and more flexible? My opinion is the Model-first! however I want to know your opinion? thanks! Read this: EF 4.1. Which way to go? It goes through the permutations based on your preferences and situation. My opinion mimics what is stated. If you don't have an existing database and dislike visual designers, code first is for you. If you do have an existing database, database first makes sense. Model first I in general avoid as the cases

Say I have a table called Users, which contains your typical information: Id, Name, Street, City--much like in the example here: http://weblogs.asp.net/manavi/archive/2010/12/11/entity-association-mapping-with-code-first-part-1-one-to-one-associations.aspx . Among other things, this article states: "Code First has a concept of Complex Type Discovery that works based on a set of Conventions. The convention is that if Code First discovers a class where a primary key cannot be inferred, and no primary key is registered through Data Annotations or the fluent API, then the type will be