Microsoft SQL Server 2012 Internals

Chapter 11. The Query Optimizer

Conor Cunningham

The Query Optimizer in Microsoft SQL Server 2012 determines the query plan to be executed for a specific SQL statement. Because the Query Optimizer doesn’t have a lot of exposed features, it’s not as widely understood as some of the other components in the SQL Server Engine. This chapter describes the Query Optimizer and how it works. After reading this chapter, you should understand the high-level optimizer architecture and be able to conclude why a particular plan was selected by the Query Optimizer. By extension, you should be able to troubleshoot problem query plans in cases when the Query Optimizer might not select the desired query plan and how to affect that selection.

This chapter is split ...