public void FindAllPlayersNotInRepo() { var repo = new MongoRepository(); var posters = repo.FindAllPosts().Select(p => p.Poster).Distinct(); var playerNames = repo.FindAllPlayers().Select(p => p.Name); var postersNotInRepo = posters.Where(p => !playerNames.Contains(p)); repo.EnsurePlayersInRepo(postersNotInRepo, "1"); }