When you encounter a performance problem, the first step is to determine what is causing it. There may be several causes for poor performance, so you should keep an open mind when looking for causes. The focus of this chapter is to find queries that may contribute to the poor performance or that may become a problem in the future when the load and amount of data increase. Still, as discussed in Chapter 1, you need to consider all aspects of your system, and often it may turn out to be a combination of factors that causes the problem.
This ...
