I imported json data from mysql using this command :
mongoimport --db your --collection categories categories.json --type json
I think RECORDS is coming from your mysql, please check your JSON file by opening it in editor like sublime.
Your Answer to export from mysql to mongo with JSON Objects:
Install Gem :
gem install mysql2xxxx
Then run :
mysql2json --user=root --database=yourdb --execute "select * from categories" > cat.json
So after run above command you will get clean records in json format, don't know how you are importing but i don't think RECORDS should come.
After done this you can use :
mongoimport --db your --collection categories cat.json --type json
Hopefully this will work.