Rails 3 and existing DB2 Datawarehouse

I work at a school and our student information is held in a DB2 database.  I have completed my first rails 3 app and I'm very interested in getting rails speak to the datawarehouse.  I've been trying to read online about the topic and the more I read the more confused I get.

I see IBM has a multitude of software options for connecting (IBM DATA Runtime, DATA Server Client, etc) and I see there is a IBM_DB2 gem.  There's a nice tutorial at

http://programmingzen.com/rubypython-and-db2-drivers/

That explains some if not all the process, but it requires you to install the DB2 express version locally.  I'm just trying to use my existing database, I have all the ODBC settings.

Any direction or thoughts would be appreciated.