Question

I have followed this guide Using Models In Your Migrations. Now I want to add a new column called suspect type boolean into Question table, it will have default value is false, and I want to update records have created too. This is my migration file:

class AddSuspectToQuestions < ActiveRecord::Migration
  class Question < ActiveRecord::Base
  end

  def change
    add_column :questions, :suspect, :boolean, default: false
    Question.reset_column_information
    Question.all.each do |question|
      question.update_attributes!(suspect: false)
    end
  end
end

But when I run rake db:migrate, it has error:

==  AddSuspectToQuestions: migrating ==========================================
-- add_column(:questions, :suspect, :boolean, {:default=>false})
   -> 0.3782s
rake aborted!
An error has occurred, this and all later migrations canceled:

Can't mass-assign protected attributes: suspect

I think it needs attr_accesible :suspect, so I added it in Question model, but I still has same error when I run migrate again. I have set this in application.rb too:

config.active_record.whitelist_attributes = true

Anyone has met this problem?

Answer 1

it doesnt work, since you are overwriting the Question Class in your migration.

Remove

class Question < ActiveRecord::Base
end

and try it again.