demo_app/my_platform/db/migrate/20170203122422_drop_state_columns_from_term_reports.your_platform.rb
# This migration comes from your_platform (originally 20170203122300)
class DropStateColumnsFromTermReports < ActiveRecord::Migration[4.2]
def change
remove_column :term_reports, :submitted_at
remove_column :term_reports, :accepted_at
remove_column :term_reports, :rejected_at
end
end