rails-db:tldr:f704a

The "rails db:setup" command is used in Ruby on Rails framework to set up a database for a Rails application.

Specifically, the "db:setup" task is a predefined rake task provided by Rails. Rake is a build automation tool in Ruby, and it allows you to define and execute tasks within your Rails application.

When you run "rails db:setup" in your command line, it performs the following steps:

1. It creates the database specified in your application's database configuration file (config/database.yml), if it doesn't already exist.
2. It loads the database schema (db/schema.rb) into the newly created database.
3. It seeds the database with the data specified in the seeds.rb file (db/seeds.rb), if one exists. The seeds file usually contains initial data or sample data to populate the database.

In summary, "rails db:setup" creates the database, sets up the schema, and optionally seeds the data, all in one command. It's typically used when setting up a new development or production environment or when resetting the database for a clean slate.