如何在Rails5中调用rake任务中的迁移

Question

在Rails 5中，我无法再使用rake任务迁移不同目录中的文件。我收到错误ActiveRecord::UnknownMigrationVersionError: No migration with version number 20180209214145。

知道如何在Rails 5中做到这一点？我认为行ActiveRecord::Migrator.migrations_paths = ['db/manual_migrate']不再按预期工作，但我不太确定如何修复它。

  desc 'Run db:migrate:up on a task we wish to migrate manually (e.g. not on all servers).' \
    'VERSION is required.'
  task manual_migrate: [:environment, :load_config] do
    raise 'VERSION of migration is required for this task!' unless ENV['VERSION']
    default_paths = ActiveRecord::Migrator.migrations_paths
    ActiveRecord::Migrator.migrations_paths = ['db/manual_migrate']
    begin
      Rake::Task['db:migrate:up'].invoke
    ensure
      ActiveRecord::Migrator.migrations_paths = default_paths
    end
  end