Hey,
The command-line interface doesn’t exist.
But it’s possible to use your own server for managing the data. For instance, you can set up an HTTP server using whatever technology you like (with any kind of interface you like), and provide a public API to manage the data. Then, on your site, you can create a back-end module consisting of functions that call your public API using wix-fetch - Velo API Reference - Wix.com and use it in your page code instead of the dataset.