“Mirror mirror on the wall, who's the fairest server of all?” This week’s column is about database-sizing tools from Dell and HP in particular, but is applicable to any performance-sizing tool that takes a one-size-fits-all approach to sizing databases. My kids--especially Emily, who is six--love Snow White. Needless to say I’ve seen the movie a gazillion times. I hope you can appreciate my gut reaction that relying on a generic Web-based sizing tool is a bit like asking a magic mirror for help.

Recently, both Dell and HP released tools to help you size hardware environments for SQL Server solutions. Dell’s tool is called SQL Advisor and is available at http://www.dell.com/content/topics/global.aspx/tools/advisors/sql_advisor?c=us&cs=555&l=en&s=biz. HP has four different sizing tools based on the type of solution and hardware you’re considering. The HP tools are
· HP ProLiant server data mart sizer for Microsoft SQL Server 2005
· HP Business Intelligence Sizer for Microsoft SQL Server 2005
· HP ProLiant server transaction processing sizer for Microsoft SQL Server 2005 (x64)
· HP Integrity server transaction processing sizer for Microsoft SQL Server 2005 (64-bit)

You can find links to each of these tools at http://h71028.www7.hp.com/enterprise/cache/3887-0-0-0-121.html. Note that you'll have to create a free HP Web site login account to access the tools. Personally, I detest having to do that, but hey, that’s just me.

Both Dell's and HP's tools ask you a series of questions, and when you've answered them all, out pops a list of recommended solutions that will meet your needs as determined by the “magic mirror on the wall,” as I like to think of it. I understand that properly sizing database solutions is hard. I also understand that customers, especially novice customers, are drawn to the simplicity of filling out a form and then being told "here is what you need." However, I can’t help but feel that this situation is one in which you get what you pay for. I’ll admit that I’m biased. I’ve been a performance tuning geek for more than a decade, and I’ve made my fair share of money helping customers decide what types of servers will meet their needs. Perhaps I have a vested interest in convincing unwitting customers that relying on an expensive consultant is the only safe way to buy "the right server." But I’ve seen way too many customers who have bought what the vendor told them or what a tool advised them to buy--and parting with a large amount of cash (larger than the consulting fee of a competent tuning expert, I might add)--only to end up with a server that doesn't meet their needs. Trust me, it’s no fun being the person in a company who has approved a five-, six-, or seven-figure expenditure only to have to say "oops" a short time later.

I know that database-sizing tools will help some people. And running these tools isn’t an utter waste of time as a starting point. But like the old adage says, sometimes you get what you pay for, and free advice from a vendor who wants to sell you hardware should be taken with a grain of salt. Play with the tools. Use them to establish a frame of reference. But please do proper due diligence with your internal experts, or hired performance tuning guns if your internal team doesn’t have that skill set, to make sure that the magic mirror on the wall isn’t suggesting a solution that might end up tasting like a poison apple.