Unfortunately, enums are not natively supported on EF 4.1. Here’s one rather known article on how to deal with them: Faking enums on EF 4. It does, however, require a wrapper. There’s a simpler way to map enums in EF 4 however: just create an int property on your class to represent the int value … Read more
There is no default configuration for eager loading. You must always define Include or create some reusable method which will wrap adding include. For example you can place similar method to your context: public IQueryable<MyEntity> GetMyEntities() { return this.MyEntities.Include(e => e.SomeOtherEntities); }
One-to-one foreign key associations are not supported by Entitiy Framework. You must remove the foreign key and use shared primary keys (primary key of the dependent is its foreign key to the principal at the same time): public class StandardRack { public int Id {get;set} public StandardRelay StandardRelay {get;set} } public class StandardRelay { public … Read more
That’s because you cannot define database view using code-first approach. Database view is database construct which uses SQL Query on top of existing tables / functions. You can’t define such constructs using code first. If you want view you must create it manually by executing CREATE VIEW SQL script for example in custom initializer – … Read more
I first clear the existing ingredients collection in the product entity and than add the updated list of ingredients again. Well, this is kind of brute-force-attack to update the child collection. EF doesn’t have any magic to update the children – which means: adding new children, deleting removed children, updating existing children – by only … Read more
Possible reason why you don’t get cascading delete is that your relationship is optional. Example: public class Category { public int CategoryId { get; set; } } public class Product { public int ProductId { get; set; } public Category Category { get; set; } } In this model you would get a Product table … Read more
I believe, it is not possible to define the relationship only with data attributes. The problem is that EF’s mapping conventions assume that Creator and Modifier are the two ends of one and the same relationship but cannot determine what the principal and what the dependent of this association is. As far as I can … Read more
It is theoretically correct but SQL server (not Entity framework) doesn’t like it because your model allows single employee to be a member of both First and Second team. If the Team is deleted this will cause multiple delete paths to the same Employee entity. This cannot be used together with cascade deletes which are … Read more
Let’s assume that you have a collection of the properties to be excluded: var excluded = new[] { “property1”, “property2” }; With EF5 on .NET 4.5 you can do this: var entry = context.Entry(obj); entry.State = EntityState.Modified; foreach (var name in excluded) { entry.Property(name).IsModified = false; } This uses a new feature of EF5 on … Read more
You can mark both ActivityID and ActivityName properties with Key annotation or you can use fluent API as described by @taylonr. Edit: This should work – composite key defined with annotations requires explicit column order: public class ActivityType { [Key, Column(Order = 0)] public int ActivityID { get; set; } [Key, Column(Order = 1)] [Required(ErrorMessage … Read more