class OverviewRoleIds < ActiveRecord::Migration def up # return if it's a new setup return if !Setting.find_by(name: 'system_init_done') create_table :overviews_roles, id: false do |t| t.integer :overview_id t.integer :role_id end add_index :overviews_roles, [:overview_id] add_index :overviews_roles, [:role_id] Overview.connection.schema_cache.clear! Overview.reset_column_information Overview.all.each { |overview| next if overview.role_id.blank? overview.role_ids = [overview.role_id] overview.save! } remove_column :overviews, :role_id end end