Of the three techniques, I strongly prefer the third because the first and second techniques force the Rails application into the picture.

在这三种技巧中，我更喜欢第三种，因为第一和第二种技巧都会将 Rails 应用程序牵扯进来。

Many Rails developers now use stubs or mocks to take the database out of the picture, forming lightning-fast functional tests.

现在很多Rails开发人员都使用stub和mock替代数据库，这就使功能测试变得十分轻快。

Since Rails is now in the picture, it's slightly slower than page caching, but there's an upside.

由于现在使用了Rails，因此动作缓存的速度要比页面缓存慢一些，但其优点还是很明显的。