这些都是在database.yml中设置的：

test:
  ...
  database: my_app_test

test_my_second_connection:
  ...
  database: my_second_connection_test

第二个数据库通过建立连接连接在模型类中.

根据manual of database_cleaner,我可以在spec / spec_helper.rb文件中使用以下设置：

require 'database_cleaner'

RSpec.configure do |config|

  config.before(:suite) do
    DatabaseCleaner.strategy = :transaction
    DatabaseCleaner[:active_record,{:connection => :test_my_second_connection}].strategy = :transaction
  end

  config.before(:each) do
    DatabaseCleaner.start
    DatabaseCleaner[:active_record,{:connection => :test_my_second_connection}].start
  end

  config.after(:each) do
    DatabaseCleaner.clean
    DatabaseCleaner[:active_record,{:connection => :test_my_second_connection}].clean
  end

end

此外,我不得不使用测试套件非事务性固定装置的一些部分.所以我不得不添加元信息：db_truncate =>为了在测试运行中改变策略,我的规范和这样的设置是真的

config.before(:suite) do
  DatabaseCleaner.strategy = :transaction
  DatabaseCleaner[:active_record,{:connection => :test_my_second_connection}].strategy = :transaction
end

config.before(:each) do
  if example.Metadata[:db_truncation]
    DatabaseCleaner.strategy = :truncation
    DatabaseCleaner[:active_record,{:connection => :test_my_second_connection}].strategy = :truncation
  else
    DatabaseCleaner.start
    DatabaseCleaner[:active_record,{:connection => :test_my_second_connection}].start
  end
end

config.after(:each) do
  DatabaseCleaner.clean
  DatabaseCleaner[:active_record,{:connection => :test_my_second_connection}].clean
  if example.Metadata[:db_truncation]
    DatabaseCleaner.strategy = :transaction
    DatabaseCleaner[:active_record,{:connection => :test_my_second_connection}].strategy = :transaction
  end
end