Your problem is only partly related to Rails, but here is are some
topics that you need to research:
1. How to run Cron jobs in your Linux distribution:
* Have a look at "man crontab", "crontab -e", crontab -l"
2. You need to either call a rake task from your cron job, or, you
write a simple shell script.
Maybe a good start would be looking at the following projects:
* I also wrote a small import/export tool for a Rails application:
Maybe it's helpful, note that you can load your rails environment for
any script by using: