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Entity Framework model issue

I am having some strange issues, I am attempting to pull a record out of the database and it seems like most of it is null even know if I manually look in the DB it's populated.
Model
public class AdminConfiguration : Entity // Entity is an abstract class containing an ID
{
public bool Authentication { get; set; }
public List<ApplicationConfiguration> ApplicationConfiguration { get; set; }
public List<LinksConfiguration> LinksConfiguration { get; set; }
public EmailConfiguration EmailConfiguration { get; set; }
public bool WakeOnLan { get; set; }
}
Basically any reference to another class is null The only thing that is populated is the WakeOnLan property.
Query
public AdminConfiguration Find(int id)
{
return Db.AdminConfiguration.Find(id);
}
I have a feeling I have a misunderstanding regarding how I set up the models. I am expecting the query to return me a fully populated AdminConfiguration object.

Try to set navigation properties as virtual to enable lazy loading:
public virtual List<ApplicationConfiguration> ApplicationConfiguration { get; set; }
Please refer to https://msdn.microsoft.com/en-us/data/jj193542.aspx
This enables the Lazy Loading feature of Entity Framework. Lazy
Loading means that the contents of these properties will be
automatically loaded from the database when you try to access them.

The best way to setup your model is:
public class AdminConfiguration : Entity // Entity is an abstract class containing an ID
{
public AdminConfiguration()
{
this.ApplicationConfigurations = new HashSet<ApplicationConfiguration>();
this.LinksConfigurations = new HashSet<LinksConfiguration>();
}
public bool Authentication { get; set; }
public EmailConfiguration EmailConfiguration { get; set; }
public bool WakeOnLan { get; set; }
// Navigation properties
public virtual ICollection<ApplicationConfiguration> ApplicationConfigurations { get; set; }
public virtual ICollection<LinksConfiguration> LinksConfigurations { get; set; }
}

MVC 4 EF database first Model constructor updates

I have created an MVC 4 application with EF db-first using ADO.NET Entity Data Model.
I've previously been adding data validation and updating constructors directly into the generated Model classes, but as I foresee these tables to be updated I don't want to have to add these all back in, plus I shouldn't be editing these auto generated classes anyway.
Using Metadata.cs and PartialClasses.cs from http://www.asp.net/mvc/tutorials/mvc-5/database-first-development/enhancing-data-validation I'm not sure the best way to update the default constructors for these Model classes.
Here's an example model, simplified.
Within .edmx
public partial class Campaign
{
public Campaign()
{
this.Fees = new HashSet<Fee>();
}
public int ID { get; set; }
public string Name { get; set; }
public string CreatedBy { get; set; }
public System.DateTime CreatedOnDate { get; set; }
public virtual ICollection<Fee> Fees { get; set; }
}
within ParticalClasses.cs [errors as the generated Modal class defines the default constructor]
[MetadataType(typeof(CampaignMetadata))]
public partial class Campaign
{
public Campaign()
{
this.Fees = new HashSet<Fee>();
// Non-Generated
this.CreatedOnDate = DateTime.Now;
}
}
I have other models I would also like to have other constructors with different parameters, so to simplify my question, where do I add constructors for DB first MVC as to no update the generated Model classes?

Not 100% sure about what you are trying to do, but I'll try to answer your question.
First of all, it seems that you are missing the point of the MVC: your link refers to view model validators, but you are talking about data models. Two VERY different things. There's nothing to validate in a data model - those change and are govern by what's going on in the database.
This is what I would do:
1) Create a data layer: this would hold all your entity classes.
2) Create a service layer: this will instantiate and populate the entity classes using either raw sql, or a pattern (repository pattern, for exam).
3) Create your website: this will hold your controllers, view models (they are the ones you want to validate) and views.
For your Campaign class:
public interface IEntity
{
object EntityID { get; set; }
}
public abstract class BaseEntity: IEntity
{
public abstract object EntityID { get; set; }
}
public class Campaign : BaseEntity
{
#region Properties
public int ID { get; set; }
public string Name { get; set; }
public string CreatedBy { get; set; }
public DateTime CreatedOnDate { get; set; }
public virtual List<Fee> Fees { get; set; }
#endregion
#region BaseEntity Implementation
public override object EntityID
{
get { return this.ID; }
}
#endregion
#region Constructors
public Campaign()
{
this.CreatedOnDate = DateTime.Now;
this.Fees = new List<Fee>();
}
#endregion
}
//View model
//THIS is the class you want to validate
public class CampaignViewModel
{
#region Properties
public int ID { get; set; }
[StringLength(50)]
public string Name { get; set; }
[Required]
public string CreatedBy { get; set; }
public DateTime CreatedOnDate { get; set; }
public Fee AssociatedFee { get; set; }
#endregion
#region Constructors
public CampaignViewModel()
{ }
public CampaignViewModel(Campaign data)
{
this.ID = data.ID
this.Name = data.Name;
this.CreatedBy = data.CreatedBy;
this.CreatedOn = data.CreatedOn;
this.AssociatedFee = data.Fees.Where(x=>x.Active && x.ID == this.ID);
//Just an example
}
#endregion
}
Also, you could use Fluent Validation for a more in-depth separation of concerns. (http://fluentvalidation.codeplex.com/)

EF5 Model-First, DBContext code generation and derived class

I'm creating a EF5 entity model with the designer (VS2012), and used the EF5 DbContext generator as code generation item.
My model contains an entity deriving from another (not abstract).
So let's say the base entity is called BaseEntity, and the derived entity is DerivedEntity.
Now I see in the generated context class, that there is no
Public DbSet<DerivedEntity> DerivedEntities { get; set; }
defined.
Only
Public DbSet<BaseEntity> BaseEntities { get; set; }
is defined.
Is this normal ? And if yes, how do I query the derived entities in linq ?
I'm used to query like this:
using(var ctx = new EntityContainer)
{
var q = from e in ctx.DerivedEntities <-- but this is now not possible since it doesn't exist
select e;
return q.ToList();
}
Thanks for replying.
EDIT:
As requested, generated classes posted:
public partial class Scheduling
{
public int Id { get; set; }
public string Subject { get; set; }
public System.DateTime BeginDate { get; set; }
public System.DateTime EndDate { get; set; }
}
public partial class TeamScheduling : Scheduling
{
public int TeamId { get; set; }
public Nullable<int> AssignmentId { get; set; }
public virtual Team Team { get; set; }
public virtual Assignment Assignment { get; set; }
}
public partial class EntityContainer : DbContext
{
public EntityContainer()
: base("name=EntityContainer")
{
}
protected override void OnModelCreating(DbModelBuilder modelBuilder)
{
throw new UnintentionalCodeFirstException();
}
public DbSet<Team> Teams { get; set; }
public DbSet<Location> Locations { get; set; }
public DbSet<Country> Countries { get; set; }
public DbSet<Assignment> Assignments { get; set; }
public DbSet<ProductType> ProductTypes { get; set; }
public DbSet<AssignmentPreference> AssignmentPreferences { get; set; }
public DbSet<Scheduling> Schedulings { get; set; }
}
As you see, the EntityContainer class does not contain
public DbSet<TeamScheduling> TeamSchedulings { get; set; }

This is expected when you use inheritance the way you have. context.Schedulings contains both Scheduling objects and TeamScheduling objects. You can get the TeamScheduling objects only by asking for context.Schedulings.OfType<TeamScheduling>(). Note that you cannot meaningfully use context.Schedulings.OfType<Scheduling>() to get the others: that will also include the TeamScheduling objects.
You could alternatively try context.Set<TeamScheduling>(), but I'm not entirely sure that will work.

If your intention is to have two tables come up, say a parent Scheduling entity as well as a child TeamScheduling entity that has a foreign key back to the Scheduling entity, consider using a Table-per-Type (TPT) mapping as discussed here.
In essence, you should modify your "OnModelCreating" method to have the following code:
modelBuilder.Entity<TeamScheduling>().ToTable("TeamScheduling");
This explicitly tells EF that you want to have the TeamScheduling subclass to be represented as its own table. Querying it via LINQ would be simple as you would be able to do something like the following:
var teamScheds = context.Set<TeamScheduling>().Where(s => s.Id == 1).FirstOrDefault();

Entity Framework Many to many through containing object

I was curious if it is possible to map an intermediate table through a containing object.
public class Subscriber : IEntity
{
[Key]
public int Id { get; set; }
public string Name { get; set; }
private ChannelList _subscribedList { get; set; }
public int NumSubscribedChannels { get { return _subscribedList.Count(); } }
}
public class HelpChannel : IEntity
{
[Key]
public int Id { get; set; }
public string name { get; set; }
public string category { get; set; }
public int group { get; set; }
}
I need to have a subscriber table, channel table and an intermediate table to link a subscriber to his/her channels.
Is it possible to map the list that is within the ChannelList object to the Subscriber Model?
I figured that's probably not possible and that I would need to just have a private List for EF to map. But I wasn't sure if EF will do that for private variables. Will it?
I'm hoping that is does because if it has to be public to maintain the encapsulation.

You can map private properties in EF code-first. Here is a nice description how to do it. In your case it is about the mapping of Subscriber._subscribedList. What you can't do is this (in the context's override of OnModelCreating):
modelBuilder.Entity<Subscriber>().HasMany(x => x._subscribedList);
It won't compile, because _subscribedList is private.
What you can do is create a nested mapping class in Subscriber:
public class Subscriber : IEntity
{
...
private ICollection<HelpChannel> _subscribedList { get; set; } // ICollection!
public class SubscriberMapper : EntityTypeConfiguration<Subscriber>
{
public SubscriberMapper()
{
HasMany(s => s._subscribedList);
}
}
}
and in OnModelCreating:
modelBuilder.Configurations.Add(new Subscriber.SubscriberMapping());
You may want to make _subscribedList protected virtual, to allow lazy loading. But it is even possible to do eager loading with Include:
context.Subscribers.Include("_subscribedList");

How to wrap a key with another object in entity framework / code first

I just started prototyping our existing object model in entity framework/code first and hit my first snag. Unfortunately the documentation for this seems to be very scarce.
My key is not a primitive but an object that wraps a primitive. How do I get this to work with EF/Code first:
public class EFCategoryIdentity
{
public string IdentityValue { get; private set; }
public EFCategoryIdentity(string value)
{
IdentityValue = value;
}
}
public class EFCategory
{
[Key]
public EFCategoryIdentity CategoryIdentity { get; set; }
public string Name { get; set; }
public virtual ICollection<EFProduct> Products { get; set; }
}
public class EFProduct
{
[Key]
public int ProductId { get; set; }
public string Name { get; set; }
public virtual EFCategory Category { get; set; }
}
What do I need to put here to make this work?
public class MyTestContext : DbContext
{
public DbSet<EFCategory> Categories { get; set; }
public DbSet<EFProduct> Products { get; set; }
protected override void OnModelCreating(DbModelBuilder modelBuilder)
{
modelBuilder.Entity<EFCategory>()
.// Help!
}
}
Thanks!

Entity framework can use only primitive types as keys. Every time you wrap some mapped property to separate type you are creating complex type. Complex types have some limitation
They cannot be keys
They cannot contain keys
They cannot contain navigation properties
etc.