public class Database
{
    public int ID { get; set; }
    public string name { get; set; }
    public virtual List<ElementBase> elements { get; set; }
    private string XMLpath;
}

public abstract  class ElementBase : ObservableObject
{
    [Key]
    public int ID { get; set; }

    public string name { get; set; }

    public ElementBase() { }
    public ElementBase(String name)
    {
        this.name = name;
    }

}

    public class Element : ElementBase
{
    protected string type;
    public virtual List<ElementBase> elements { get; set;}
}
    public class Attribute : ElementBase
{
    private string value;
    private byte editable;
}

public  DbSet<NWViewer.Model.Database> Databases { get; set; }

public static void add(NW.Database db)
    {
        using (var dbContext = new DatabaseContext())
        {
            dbContext.Databases.Add(db);
            dbContext.SaveChanges();
        }
    }