socialforge/db/migrate/20170218074506_create_homework_samples.rb

class CreateHomeworkSamples < ActiveRecord::Migration
  def change
    create_table :homework_samples do |t|
      t.text :input
      t.text :output
      t.references :homework_common

      t.timestamps
    end
    add_index :homework_samples, :homework_common_id
  end
end