public IQueryable <IPoster> FindByUserIdAndTourId(Guid userId, Guid tourId)
        {
            var shows = _showRepo.FindByTourId(tourId);

            var showIds = (from s in shows select s.ShowId).ToList();

            return((from p in FindAllByUserId(userId)
                    where showIds.Contains(p.ShowId.Value)
                    select p).Cast <IPoster>());
        }
        public IQueryable <ITicketStub> FindByUserIdAndTourId(Guid userId, Guid tourId)
        {
            var shows = _showRepo.FindByTourId(tourId);

            var showIds = (from s in shows select s.ShowId).ToList();

            return(from ts in FindByUserId(userId)
                   where showIds.Contains(ts.ShowId.Value)
                   select ts);
        }