Eric M Russell (2/23/2016)
Assuming you could load GB of disk storage, GB of RAM, Windows, and SQL Server, a Raspberry PI would be severely under powered for even single user testing purposes. If what you want is an isolated sandbox, then consider running a VM like VirtualBox or VMware on your work / home PC.
This is if you need the Raspberry to be the host.
As a test box, it could be a client, with queries or simulating load. In that case, it would be an interesting use, with multiple Raspberry PIs.