## The problem:
$ rake db:migrate
(in ...)
rake aborted!
#28000Access denied for user 'root'@'localhost' (using password: YES)

## database.yml
development:
  adapter: mysql
  database: foo_development
  host: localhost
  username: root
  password: root

## can login from cmd line
$ mysql -u root -p foo_development
Enter password:
Welcome to the MySQL monitor.  Commands end with ; or \g.