How can I use different databases in a Rails application?

How can I use different databases in a Rails application?

You can use multiple databases in Rails by configuring them in your database.yml file and using ActiveRecord's multi-database features.

Can you give me an example of how to set that up?

Sure! In your database.yml, you can define multiple databases like this:

production:
  primary:
    adapter: postgresql
    database: primary_db
  secondary:
    adapter: postgresql
    database: secondary_db

Then, you can specify which database to use in your models.

What about migrations? How do they work with multiple databases?

Migrations can be run on specific databases by using the ActiveRecord::Migration class and specifying the database connection. You can also create separate migration files for each database.