Schema specified is not valid. Errors: The relationship was not loaded because the type is not available

Question

I wish to reference the OrderAddress model twice in my Order model; once as a ShippingAddress and once as a Billing

Answer 1

I got the same error using database first: "The relationship was not loaded because the type ... is not available". The problem was the model in the solution was outdated. To fix the problem:

• Double click on edmx file under Solution.
• Right click on it.
• Select "Update Model from Database...".
• Click on the "Refresh" tab.
• Click on the Finish button.

Your edmx now should be updated with the latest database changes.

Answer 2

I got one solution here! if you are using EF then do following,

Open model.edmx then right click on it and update model from database. finally build application and run it.

Answer 3

You need to change your OrderAddress entity and your Fluent API mappings to the following:

OrderAddress:

public class OrderAddress : BaseModel
{
    ...
    public virtual ICollection<Order> BillingOrders { get; set; }
    public virtual ICollection<Order> ShippingOrders { get; set; }
    ...
}

Fluent API:

protected override void OnModelCreating(DbModelBuilder modelBuilder)
{
    base.OnModelCreating(modelBuilder);

    modelBuilder.Entity<Order>()
                .HasRequired(m => m.ShippingAddress)
                .WithMany(t => t.ShippingOrders)
                .HasForeignKey(m => m.ShippingAddressId)
                .WillCascadeOnDelete(false);

    modelBuilder.Entity<Order>()
                .HasRequired(m => m.BillingAddress)
                .WithMany(t => t.BillingOrders)
                .HasForeignKey(m => m.BillingAddressId)
                .WillCascadeOnDelete(false);
}

Check this SO post for more, it is about the same problem as yours.

Answer 4

This is common in self relation entities. in this case:

1-check to have ICollection, List, ... relation collection for each relation.

2-check name of relation collections.

3-in code first, check your EntityTypeConfiguration

Answer 5

The error is a little cryptic, so I'm not sure if this is the reason you're getting that particular error, but I do know it will cause some error, so you can start by fixing this:

What you have is two one-to-many relationships to the same model on one class. That's not a problem per se, but you have to treat them as separate. In other words, they can't both have a opposite relationship of Orders, because relationally, there's no way to know which foreign key relationship should populate that list. If you simply change your fluent API definition to something like .WithMany(t => t.Orders_Shipping) and .WithMany(t => t.Orders_Billing), I think that will clear up your error.

Answer 6

Had this issue. I believe it is something to do with the web service. My solution was after updating the service reference and the config operation took place. the problem went away. hope this helps.