Guide rails, database?

I would like the seed/database used in the guide to be available, so people who are starting out like me understand where the data comes from. Is this available in any repository? Example taken from the guide (active_record_querying):

customer = Customer.find(10)
=> #<Customer id: 10, first_name: "Ryan">

There is no seed data available for the guides, much of the documentation is written ad-hoc, usually by someone testing the code in their terminal before committing.

It’s an interesting idea though, I just think it would be difficult to maintain a repository of models and tests just for the guides and could easily drift. Executable documentation isn’t too far fetched from that, but yeah I have no idea how that could be implemented or maintained.