migrate

# File activerecord/lib/active_record/migration.rb, line 548
      def migrate(migrations_paths, target_version = nil, &block)
        case
          when target_version.nil?
            up(migrations_paths, target_version, &block)
          when current_version == 0 && target_version == 0
            []
          when current_version > target_version
            down(migrations_paths, target_version, &block)
          else
            up(migrations_paths, target_version, &block)
        end
      end