Question

I prepare to develop one project, which has no UI. The project just need to interact with database, so is there any example for reference ？

Answer 1

Does your app have ties to a Rails-based app and need to read the Rails configuration files? Or, is it entirely stand-alone and have no Rails interaction?

ActiveRecord is OK for that, but if I don’t need Rails compatibility I use Sequel. It’s a great ORM that I find to be much more flexible.

If you need Rails compatibility and want to use ActiveRecord, look into using rails runner. From the docs:

runner runs Ruby code in the context of Rails non-interactively. For instance:

$ rails runner "Model.long_running_method"

Rails runner is for command-line apps that don’t need the HTTPd server or user-interface of Rails. I use them for things like an app that runs daily to ftp files from a site for analysis. It has to write to the database, so it has access to all the models I’ve defined, but it never needs to present anything to the user since it is invisible to them.