RavenDB.Projection.OneToManyRelationship

// documents: Place
public class Place{
	public int Id{get;set;}
	public string Name{get;set;}
	public IList<int> PhotoIds{get;set;}
}

// documents: Photo
public class Photo{
	public int Id{get;set;}
	public string Title{get;set;}
}

// index definition
public class PlaceWithCoverPhotoIndex : AbstractIndexCreationTask<Place> {
	
    public PlaceWithCoverPhotoIndex() {
    	
        Map = places =>
            from place in places
            let firstPhotoId = place.PhotoIds.FirstOrDefault()
            select new { CoverPhotoId = firstPhotoId };
            
        TransformResults = 
       	    (database, places) =>
            from place in places
            let firstPhotoId = "photos/" + place.PhotoIds.FirstOrDefault()
            let cover = database.Load<Photo>(firstPhotoId)
            select new {
                    Id = place.Id,
                    Name = place.Name,
                    CoverPhoto = new {
                        PhotoId = cover.Id,
                        Title = cover.Title,
                    }
            };

    }
}

// usage
public void Client(){
    using(var session = store.OpenSession()){
        var list = session.Query<Place,PlaceWithCoverPhotoIndex>().ToList(); // returns empty list
    }
}

Hi, please my name is Morgan, can you please teach me how i can create stuff like this on my own? please