The <a href="http://www.infoworld.com/d/data-explosion/no-sql-new-databases-new-applications-400">NoSQL movement</a> has spawned a slew of alternative data stores, all of which attempt to fill voids left by traditional relational database implementations. But while it's easy to fit the various relational databases (MySQL, Oracle, DB2, and so on) under a single categorical umbrella, the NoSQL world is much more diverse, and the NoSQL label is too general. NoSQL data stores such as MongoDB and Cassandra are so vastly different from each other that apples-to-apples comparisons are practically impossible. Thus, within the world of NoSQL, there are subcategories such as key-value stores, graph databases, and document-oriented stores.
Stories by Andrew Glover
Heroku is a pure platform as a service -- that is, the entire infrastructure is managed by Heroku and not by you. As such, deploying a Ruby application, whether or not it is Rails based, is practically effortless. Deployment, in fact, is performed as a part of a regular SCM (software configuration management) sync via <a href="http://www.infoworld.com/d/application-development/torvaldss-git-the-it-technology-software-version-control-167799">Git, an innovative, freely available, and quite popular distributed source code management system pioneered by Linus Torvalds</a>, the creator of Linux.
Although code deployment might not be as easy with Engine Yard as with <a href="http://www.infoworld.com/d/application-development/infoworld-review-heroku-cloud-application-platform-180342">Heroku</a>, the Engine Yard platform is dramatically more tunable. In fact, in many ways, Engine Yard is closer to an infrastructure as a service (IaaS) than a platform as a service (PaaS). Engine Yard provides a base infrastructure tuned to run Ruby applications, but the rest is up to you. Engine Yard does offer <a href="http://www.infoworld.com/d/application-development/torvaldss-git-the-it-technology-software-version-control-167799">Git integration</a>; however, deployment is not executed via a push, as in Heroku, but rather via Engine Yard's suite of tools and its extensive dashboard, which can sync with a Git repository.
In the world of Ruby development, there are two primary cloud-based, platform-as-a-service offerings: Engine Yard and Heroku. Both provide an easy-to-scale, managed hosting environment, both are built on Amazon EC2, and both have a long and intimate history with the Ruby community. Nevertheless, they offer contrasting approaches and features that will appeal to different audiences.