12:01  12:01:22  12:01:22.123
 key   0:0                                  
time   0:5   ^---^                          12:01
pair   0:5   ^---^                          12:01
 key   7:7         ^                        
time   7:15         ^------^                12:01:22
pair   7:15         ^------^                12:01:22
 key  17:17                  ^              
time  17:29                   ^----------^  12:01:22.123
pair  17:29                   ^----------^  12:01:22.123
msg         :12:01  12:01:22  12:01:22.123
format      :#  #  #
{
    "col_0": "12:01",
    "col_1": "12:01:22",
    "col_2": "12:01:22.123"
}