EF6 Linq Navigation properties are always null

Question

Here is the setup

I have a product table

public partial class Product
{
public uint Id {get; set;}
public uint TypeId {get; set;}
public virtual ProductType ProductTypeNavigation { get; set; } = null!;
}

public partial class ProductType
{
public uint Id {get; set;}
public string? Caption { get; set; }
}

context for _db
public virtual DbSet<Product> Products { get; set; } = null!;

linq query
Product product = _db.Products.FirstOrDefault(x=>x.Id = 1);

What do I need to do in order for ProductTypeNavigation to be populated? It always returns null. I can see product.TypeId is populated correctly. Tried using .first instead of firstordefault still null. Tried .Where().ToList().First() same result. Also tried installing lazyload proxies still null.

Answer 1

Include the ProductTypeNavigation property in the LINQ expression.

var data = context.Products  
    .Include(p => p.ProductTypeNavigation)  
    .ToList();  
  

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