Rails - Database Commands

Rails database commands are a set of tools for managing the database for a Ruby on Rails application. These commands allow developers to create, drop, and reset databases, as well as run database migrations and seed the database with data.

These commands can be run from the command line, and can be useful for tasks such as setting up a new database, modifying the database structure, and loading initial data into the database.

Create a Database

The rails db:create command is used to create a new database for your Rails application. It creates the database specified in your config/database.yml file for the current environment.

For example, if you are using SQLite and you run rails db:create, it will create a new file in the db directory for your database. If you are using a different database, such as MySQL, it will create a new database on the database server.

This command is typically run as part of the setup process for a new Rails application. It is also useful when you want to create a new database for an existing application, such as when you are setting up a staging or production environment.

Create Databases for All 3 Environments

The rails db:create:all command is similar to the rails db:create command, but it creates databases for all environments specified in your config/database.yml file.

For example, if you have a development, test, and production environment defined in your database.yml file, running rails db:create:all will create databases for all three environments.

This command is useful when you want to create all of the databases for an application at once, rather than creating them one at a time for each environment.

Drop a Database

The rails db:drop command is used to delete the database for your Rails application. It drops the database specified in your config/database.yml file for the current environment.

For example, if you are using SQLite and you run rails db:drop, it will delete the file in the db directory for your database. If you are using a different database, such as MySQL, it will delete the database on the database server.

This command is typically used when you want to completely remove the current database and start from scratch. It is also useful when you want to delete the database for an existing application, such as when you are setting up a staging or production environment.

Drop Databases for All 3 Environments

The rails db:drop:all command is similar to the rails db:drop command, but it drops databases for all environments specified in your config/database.yml file.

For example, if you have a development, test, and production environment defined in your database.yml file, running rails db:drop:all will drop databases for all three environments.

This command is useful when you want to delete all of the databases for an application at once, rather than deleting them one at a time for each environment.