Added selectivity
Added selectivity


Former-commit-id: 49390973e95b1586d242f3b08228b1447847ce5c
larryxiao/peloton-1,amaliujia/CMUDB-peloton,larryxiao/peloton-1,larryxiao/peloton,ranxian/peloton,larryxiao/peloton-1,omegaga/peloton,larryxiao/peloton-1,omegaga/peloton,larryxiao/peloton-1,omegaga/peloton,omegaga/peloton,larryxiao/peloton,amaliujia/CMUDB-peloton,amaliujia/CMUDB-peloton,ranxian/peloton,larryxiao/peloton,omegaga/peloton,omegaga/peloton,amaliujia/CMUDB-peloton,amaliujia/CMUDB-peloton,larryxiao/peloton,ranxian/peloton,ranxian/peloton,larryxiao/peloton,amaliujia/CMUDB-peloton,omegaga/peloton,larryxiao/peloton-1,amaliujia/CMUDB-peloton,ranxian/peloton,ranxian/peloton,larryxiao/peloton,larryxiao/peloton-1,larryxiao/peloton