1,2,3,4,five,six,7
 key   0:0                       
 num   0:1   ^                   1
 val   0:1   ^                   1
pair   0:1   ^                   1
 key   2:2    ^                  
 num   2:3     ^                 2
 val   2:3     ^                 2
pair   2:3     ^                 2
 key   4:4      ^                
 num   4:5       ^               3
 val   4:5       ^               3
pair   4:5       ^               3
 key   6:6        ^              
 num   6:7         ^             4
 val   6:7         ^             4
pair   6:7         ^             4
 key   8:8          ^            
word   8:12          ^--^        five
 val   8:12          ^--^        five
pair   8:12          ^--^        five
 key  13:13              ^       
word  13:16               ^-^    six
 val  13:16               ^-^    six
pair  13:16               ^-^    six
 key  17:17                  ^   
 num  17:18                   ^  7
 val  17:18                   ^  7
pair  17:18                   ^  7
msg         :1,2,3,4,five,six,7
format      :#,#,#,#,#,#,#
{
    "col_0": 1,
    "col_1": 2,
    "col_2": 3,
    "col_3": 4,
    "col_4": "five",
    "col_5": "six",
    "col_6": 7
}