Added aggregate
Added aggregate


Former-commit-id: 9254fcbdb0eb734db2966614cadef14513205e22
larryxiao/peloton,omegaga/peloton,omegaga/peloton,amaliujia/CMUDB-peloton,ranxian/peloton,omegaga/peloton,larryxiao/peloton,ranxian/peloton,ranxian/peloton,amaliujia/CMUDB-peloton,larryxiao/peloton-1,larryxiao/peloton-1,larryxiao/peloton,amaliujia/CMUDB-peloton,omegaga/peloton,omegaga/peloton,ranxian/peloton,amaliujia/CMUDB-peloton,amaliujia/CMUDB-peloton,larryxiao/peloton-1,amaliujia/CMUDB-peloton,larryxiao/peloton-1,larryxiao/peloton,larryxiao/peloton-1,larryxiao/peloton,larryxiao/peloton-1,omegaga/peloton,larryxiao/peloton,ranxian/peloton,larryxiao/peloton-1,amaliujia/CMUDB-peloton,larryxiao/peloton,omegaga/peloton,ranxian/peloton