1 2 3 4 5 6 7 8"ts","dur","a","b" 9100,150,111,111 10250,50,111,"[NULL]" 11300,100,111,222 12400,100,111,333 13500,50,222,333 14600,50,333,333 15650,50,333,"[NULL]" 16900,100,444,"[NULL]" 17