Adding a column to an existing table in a Rails migration

Question

I have a Users model which needs an :email column (I forgot to add that column during the initial scaffold).

I opened the migration file and added

Answer 1

Sometimes rails generate migration add_email_to_users email:string produces a migration like this

class AddEmailToUsers < ActiveRecord::Migration[5.0]
  def change
  end
end

In that case you have to manually an add_column to change:

class AddEmailToUsers < ActiveRecord::Migration[5.0]
  def change
    add_column :users, :email, :string
  end
end

And then run rake db:migrate