Heroku copies DB instances? How is this possible?

I put my front end React app on Netlify and my back end on Heroku. I then ran around looking for a place to move my local postgres database, and was shocked that my app was already working: https://reporting-area.netlify.com/

How is this possible? All that fake data is only in my local database unless it was copied somewhere in the process (react build step? netlify? heroku?)

Netlify and Heroku both seem to clone git branches which I don’t think have any database details.

Anyone know how this is happening?

It’s worth nothing that during that initial load is when the db is accessed and the data is sent to the front end. From there the front end stores the data in state and simply manipulates it depending on the report.

EDIT: Never mind, the backend is just accessing my localhost