sample_02.csv

id,account,time,purchase,comment,json_column
1,32864,2015-01-27 19:23:49,20150127,embulk,{"k":true}
2,14824,2015-01-27 19:01:23,20150127,embulk jruby,{"k":1}
3,27559,2015-01-28 02:20:02,20150128,"Embulk ""csv"" parser plugin",{"k":1.23}
4,11270,2015-01-29 11:54:36,20150129,NULL,{"k":"v"}
5,53231,2015-01-30 13:48:12,20150130,NULL,{"k":"2015-02-03 08:13:45"}