I have an AlbumArtist class (which is my EF Entity):

public class AlbumArtist : IEquatable<AlbumArtist>
{
    public int Id { get; set; }

    public string Title { get; set; }

    public virtual List<Album> Albums { get; set; }

    public bool Equals(AlbumArtist albumArtist)
    {
        return Title.Equals(albumArtist.Title);
    }

    public override int GetHashCode()
    {
        return Title.GetHashCode();
    }
}

And an Album class (which is my EF Entity too):

public class Album : IEquatable<Album>
{
    public int Id { get; set; }

    public string Title { get; set; }

    public virtual List<AlbumArtist> AlbumArtists { get; set; }

    public bool Equals(Album album)
    {
        return Title.Equals(album.Title);
    }

    public override int GetHashCode()
    {
        return Title.GetHashCode();
    }
}

So, as you see, I have many-to-many relationship.

I create one list, populate it, than save it with DbContext, then I create and populate the second list. And then I try to merge that two lists (one from DbContext, second from the local variable) and save the result to DbContext as well (insert new entities and update existing).

I have the following data in my two lists:

--Infected Mushroom
----Classical Mushroom
----Converting Vegetarians
...



--Infected Mushroom
----The Gathering ‎
----Converting Vegetarians
--Skazi
...

And I try to get the following data:

--Infected Mushroom
----Classical Mushroom
----The Gathering ‎
----Converting Vegetarians
--Skazi
...

Please help me to write some LINQ query to achieve my goal.

Thanks!