Yelp data file type

I was having the same issue. Turns out that the file inside the tar (the one without the extension) is a tar file as well - so the download is basically a tar file inside a tar file. After extracting the original file, add the tar extension to it, and then extract that. After extracting that, you'll have all the different json files for the data set.

The github project for Yelp dataset examples has a few samples, one of them is "json_to_csv_converter" which should help you do what you're asking for.

Yelp's Academic Dataset Examples

Let me know if this helps!