Extend a database-backed web application

Setup

First of all, to get everything set up

• Fork this repo to your GitHub account
• Clone your forked repo to your machine
• cd into the directory and install the dependencies by doing bundle
• Set up the database by doing rake setup
• Seed the database with records by doing rake seed_db
• Start the server by doing rackup
• Explore the app in your browser!

The challenge

1. Open country_data.rb in your text editor. This is the only file you need to edit.
2. Read the code in the first three methods .all, .european_countries and .all_data_sorted_by_population_increasing_order
3. Note down anything you don't understand and investigate what's going on. You could use some of your debugging tools here.
4. Find the empty methods and add code to perform the queries described (by the names of the methods). Don't worry about testing this time – focus on implementing the DB queries.