In ch 16, Iteration K1, p235 in the PDF, the reader is directed to update database.yml with:
production: adapter: mysql encoding: utf8 reconnect: false database: depot_production pool: 5 username: username password: password host: localhost
After this change and running
rake db:setup RAILS_ENV="production"
I get: rake aborted! uninitialized constant Mysql
I changed the adapter value from mysql to mysql2 and the migration was successful.