Chapter 32. Parameter sniffing: your best friend... except when it isn’t
Lots of people have heard the phrase parameter sniffing. Usually it’s heard in conjunction with some horrific performance problem that has occurred within their system. But what most people don’t know is that parameter sniffing is a process that’s occurring all the time within your servers, and most of the time it’s helping you. Only sometimes does parameter sniffing lead to problems, but when it does create a problem, it’s a big one. My goal is to show you what parameter sniffing is and how it’s constantly helping your database applications run better. You’ll also learn how parameter sniffing can go wrong and why it happens. I’ll be able to show you several ways to fix parameter sniffing when it goes wrong and which are the better choices depending on your situation. But, hopefully, the most important thing you’ll take away from this chapter is that parameter sniffing is a desirable behavior that’s useful to you and your systems...except when it isn’t.
