Can I reconfigure a live Rails application?

Is it safe to alter application settings (config.*) on a Rails application that is already running?

How can I persist the changes, preferably to a database?

Update:

I want to allow the administ开发者_如何学JAVArator to configure things like Action Mailer through an admin control panel, but I'm not sure if Rails will pick up on the changes.

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Another approach instead of querying DB is to use Environment variables.

This is how you access environment variables:

ENV['name']

You may define those variables in .bash_rc for example.