Question

I have a situation where I’d like to eager load the organization property of a user being retrieved from the DB using LINQ-to-SQL (because of my using here attempts to get the property later fail because the context’s connection is closed). The problem is that sometimes the user does not have an organization. In that case FetchUserByName returns null. Not what I want at all. Is there a way to get this to work the way I want, which is to return an instance of user whether they have an associated organization or not?

    private static void EagerLoad(DataContext ctx)
    {
        var loadOpt = new DataLoadOptions();
        loadOpt.LoadWith<User>(u => u.Organization);
        ctx.LoadOptions = loadOpt;
    }

    public User FetchUserByName(string username)
    {
        User user = null;
        using (var ctx = contextManager.GetSingleDataContext())
        {
            EagerLoad(ctx);
            user = ctx.GetTable<User>().SingleOrDefault(u => u.UserName == username && u.IsActive);
        }

        return user;
    }

Answer 1

Documenting what the fix was for others who may run into this.

LoadWith actually determines whether to use an INNER JOIN or an OUTER LEFT JOIN in the SQL created by LINQ-to-SQL by looking whether the foreign key in the data model class is nullable in the database. If it is nullable it uses the outer join.

    [Column]
    public int OrganizationId { get; set; } /*** Here is The Problem ***/

    private EntityRef<Organization> _organization;

    [Association(OtherKey = "OrganizationId", Storage = "_organization", ThisKey = "OrganizationId", IsForeignKey = true)]
    public Organization Organization
    {
        get
        {
            return this._organization.Entity;
        }
    }

Changed the one line to:

public? int OrganizationId { get; set; }

And then everything worked as expected.