Despite the ongoing tragic events, we continue the series. In the last article we reviewed the stages of query execution . Before we move on to plan node operations (data access and join methods), let's discuss the bread and butter of the cost optimizer: statistics. As usual, I use the demo database for all my examples. You can download it and follow along. You will see a lot of execution plans here today. We will discuss how the plans work in more detail in later articles. For now just pay a...