Microsoft SQL Server has been advancing technologically on every front with each new release. Having spent five years as an Oracle professional (I wrote my first technical book about Oracle) before moving to SQL Server in 1995, I spent a lot of time explaining and sometimes apologizing for the technical limitations in SQL Server when compared to Oracle. With SQL Server 2005, Microsoft finally had a product that required no apologies. This was a product that could scale to multi-terabyte database sizes and could handle tens of thousands of transactions per second. SQL Server could now handle just about anything you threw at it.
Despite these innovations, there's still one thing that Oracle has that SQL Server doesn't - Real Application Clusters (RAC). RAC promises that you instantly add new servers to the Oracle cluster, adding their processing power to the cumulative total processing power available for the database application. In a nutshell, RAC promises to deliver seemless scalability and load balancing. (The marketing claims are just that, btw. RAC is not nearly as easy to install, configure, or maintain as it should be.)
What if you'd like RAC-like capabilities for your SQL Server environment? Are you out of options? Not with Xkoto's new product called Gridscale. Gridscale virtualizes your SQL Server database(s) thereby enabling you to scale them out. As you add more servers, you get more power and improved availability. I've seen a demo presented by several members of the XKoto team and, despite my skepticism, I'm impressed. If you have extreme scalability needs or what to start with a limited amount of power today and scale up later, you should watch the on-line demo here.
As always, I welcome your comments!