[Rails] storing constant data in a separate database

Following a suggestion by Rob Biedenharn <Rob@AgileConsultingLLC.com>,
I'm setting up a separate database to hold "constant" data, ie, tables
that are not changed by my application. (Though they are occasionally
changed by an external app.)

My questions are first, followed by the recipe I used to set things up:

* What's the approved way to create and modify tables in the separate
db? I'm pretty sure rake:migrate is out of the question since there's
only one schema.rb file, but I'd like to be wrong!

* Does every subclass of Readonly need to call set_table_name (see
below)? (How un-DRY!)

* If I genuinely wanted the readonly table to be read-only, is there a
way to specify that (in Rails, not in the db, since I still need my ETL
app to update Readonly occasionally)?

Thanks in advance.

-- ff

The recipe:

== I created subclasses to ActiveRecord:

# file: app/model/readonly.rb
class Readonly < ActiveRecord::Base
establish_connection :readonly
end

# file: app/model/employee.rb
class Employee < Readonly
set_table_name self.to_s.tableize
end

=== I extended config/database.yml:

# A database to hold constant data
readonly:
adapter: mysql
encoding: utf8
reconnect: false
database: myapp_readonly
pool: 5
username: <%= ENV['MYSQL_USERID'] || "root" %>
password: <%= ENV['MYSQL_PASSWORD'] || "" %>
socket: <%= ENV['MYSQL_SOCKET'] || "/tmp/mysql.sock" %>

=== Created the database "by hand" in mysql:

mysql> create database myapp_readonly;
create database myapp_readonly;
Query OK, 1 row affected (0.53 sec)

=== Populated it with a small Employee table (cribbed from another
database):

% mysqldump -uxxx -pxxx myapp_development employees > /tmp/employees.sql
% mysql -uxxx -pxxx myapp_readonly < /tmp/employees.sql

=== Verified myapp_readonly.employees:

bash-3.2$ script/dbconsole
mysql> use myapp_readonly;
mysql> show tables;
+--------------------------+
| Tables_in_myapp_readonly |
+--------------------------+
| employees |
+--------------------------+
1 row in set (0.17 sec)
mysql> select * from employees;
+----+----------------+---------------------+---------------------+
| id | name | created_at | updated_at |
+----+----------------+---------------------+---------------------+
| 1 | Roger Dodger | 2010-06-17 00:05:52 | 2010-06-17 00:05:52 |
| 2 | Monresh Trebon | 2010-06-17 00:05:52 | 2010-06-17 00:05:52 |
+----+----------------+---------------------+---------------------+
2 rows in set (0.22 sec)

== Verified that I could read Employee records:

% script/console
>> Employee.first
=> #<Employee id: 1, name: "Roger Dodger", created_at: ...>

Cool beans!! It works.
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