如何将MySQL设置为Rails 3中的默认数据库？

I started using Rails 2 last April but stopped this June because I thought learning it when Rails 3 was released would be more practical since a lot of it was completely refactored and restructured. I used to work with Ubuntu 10.04 (with SQLite3 as the default db) but now I'm using Windows 7 and MySQL 5. I already installed the gem adapter for MySQL, but to use it I still need to tweak database.yml. Thanks.I started using Rails 2 last April but stopped