Heroic data tables

I am brand new to Heroku and am trying to get a sense of how it works for my application. My understanding is that calls to post and retrieve data from a database is through SQL data tables. I created a FREE database on Heroku and am trying to see a map of the data tables and they are nowhere to be found. How do Heroku databases work through data tables if we cannot see them?

Thank you for your help!