Using the Include Method to load related objects in EntityFramework

Question

Below is a section of my Entity Framework Model. You'll notice I have a "header" table, which is related to many "AssetHolding" records, which itself can be one of 3 types - for which im using inheritance (TpH). Please ignore the fact that all 3 inherited types look identical - this is intentional

Entity model

When editing this data, I need to pull one specific header by Id, and all associated AssetHoldings. The method to do so looks like this:

public AssetValuationHeader GetValuationHeaderById(int id)
{
    return this.AssetValuationHeaders
        .Include("AssetHoldings")
        .Where(vh => vh.Id == id)
        .FirstOrDefault();
}

This correctly loads everything highlighted with a red border in the image above.

The problem im having is that I also need to load the bit highlighted with a green border in the above image. As you can see this is only related off of one of the 3 inheritance tables.

I tried this:

public AssetValuationHeader GetValuationHeaderById(int id)
{
    return this.AssetValuationHeaders
        .Include("AssetHoldings")
        .Include("AssetHoldings.SwapAssetHoldingNotionals")
        .Where(vh => vh.Id == id)
        .FirstOrDefault();
}

A specified Include path is not valid. The EntityType 'CoreValuationModel.AssetHolding' does not declare a navigation property with the name 'SwapAssetHoldingNotionals'.

Is this even possible using the Include method? (ie, without using LazyLoading) Any workaround if not?

It doesn't work because of entity inheritance. See http://stackoverflow.com/questions/944332/entity-framework-inheritance-and-include — ken2k, Feb 23 '12 at 12:35

jim tollan · Answer 1 · 2012-02-23T12:56:28.843

jamie,

[spoiler] - this is coded from complete memory and may not actually compile at all!!

Anyway, I've had situations where I've had to load the graph a few levels deep and seem to remember doing something along the following lines:

public AssetValuationHeader GetValuationHeaderById(int id)
{
    return this.AssetValuationHeaders
        .Include("AssetHoldings")
        .Include("AssetHoldings").Select(sa => sa.SwapAssetHoldingNotionals)
        .Where(vh => vh.Id == id)
        .FirstOrDefault();
}

or:

public AssetValuationHeader GetValuationHeaderById(int id)
{
    return this.AssetValuationHeaders
        .Include("AssetHoldings")
        .Include("AssetHoldings").Include("SwapAssetHoldingNotionals")
        .Where(vh => vh.Id == id)
        .FirstOrDefault();
}

as i said, don't shoot the messenger (will check this out away from my 'phone' later)

Using the Include Method to load related objects in EntityFramework

1 Answers1