What are Ruby on Rails migrations and how do they work?

What are Ruby on Rails migrations and how do they work?

Ruby on Rails migrations are a way to alter your database schema over time in a consistent and easy way. They allow you to create, modify, and delete database tables and columns.

Can you give me an example of a migration?

Sure! A simple migration to create a 'users' table might look like this: create_table :users do |t| t.string :name t.string :email t.timestamps end.

How do I roll back a migration?

You can roll back a migration using the command rails db:rollback. This will undo the last migration that was run.

What if I want to change a column type?

You can change a column type using the change_column method in a migration, like this: change_column :users, :age, :integer.

Are there any best practices for writing migrations?

Yes, it's best to keep migrations small and focused, use descriptive names, and always test them in a development environment before running in production.