At #SQLbits, Simon Sabin (Twitter) talked about car crash queries: queries that suddenly have bad performance out of nowhere, yet if you copy/paste them into SQL Server Management Studio, they run quickly. The culprit is often parameter sniffing: the engine looks at the query and builds a plan, but if the parameters in the WHERE…Read More
My gauge of an amazing book is simple: if I’ve got a question, and I reach for the book BEFORE I search the web, then it’s an amazing book. Several times in the last two weeks, I reached for this book first.
Our QA department uses Mercury TestDirector to do load testing of our .NET web apps. The basic idea is that TestDirector runs through a set of URLs to load test an application, and it can gradually scale up the number of simultaneous sessions until the datacenter is filled with smoke. When the fire alarms go…Read More