_reducer = (state, payload) => {
                const session = _orm.session(state || _orm.getEmptyState());
                session.Yin.create(payload);
                return session.state;
            }
Note that the above only recomputes because we need to
perform a full-table scan there, even if we knew before
exactly which IDs we wanted to access. This should
be fixable by allowing arrays as filter arguments.