migrate

# File activerecord/lib/active_record/migration.rb, line 412
      def migrate(migrations_path, target_version = nil)
        case
          when target_version.nil?
            up(migrations_path, target_version)
          when current_version == 0 && target_version == 0
          when current_version > target_version
            down(migrations_path, target_version)
          else
            up(migrations_path, target_version)
        end
      end