Transfer the database from a RoR project to another one

There's a plugin called YamlDB (http://opensource.heroku.com) which
can serialize the entire contents of the database into a .yml file.
However, if your database has large tables, this solution might not be
the best, as the resulting yaml file could be extremely large.
Otherwise, your best bet might be the traditional means of dumping and
loading SQL (mysqldump, etc.).