Querying data with EF doesn't return all entities

Question

I'am currently changing a project from LINQ to SQL to LINQ to Entity. I have the following entity:

Customer -> Address

I query my database through a WCF Data Service async with this method:

public static async Task<IEnumerable<TResult>> ExecuteAsync<TResult>(this DataServiceQuery<TResult> query)
{
    var queryTask = Task.Factory.FromAsync<IEnumerable<TResult>>(query.BeginExecute(null, null), (asResult) =>
    {
        var result = query.EndExecute(asResult);
        return result;
    });

    return await queryTask;
}

If I do a query on this entity, I can access the Customer, but the address is still null:

var query = (DataServiceQuery<Customer>)client.Customer.OrderBy(session => session.LastName);
var data = await query.ExecuteAsync();
Test2.Text = data.LastName(); //returns the lastname
Test2.Text = data.First().Address.Stret; //Address is Null

I have checked the database and the foreign keys are set correctly. Why is the address null? Do I have to query another way? In LINQ to SQL it was possible to access the related entity, how can I archive this in LINQ to Entity?

Answer 1

[nkvu - moving as an answer as indicated by the original poster. Also highly recommend @RAS's answer to this question for an explanation of the different loading strategies.]

Perhaps try to use an [Expand]( http://msdn.microsoft.com/en-us/library/ee358709.aspx) call against Address when constructing your query to load related entities.