Chapter 5Overview of Changes to the Query Processing Engine

This chapter provides an overview of the changes to the query processing engine. The chapter discusses optimization goals, and outlines how to set them at the server, session, and query levels. It briefly describes the optimization criteria. Next, the chapter discusses the optimizer’s new “timeout limit” feature and shows how and why to limit the time the optimizer may spend on a particular query plan. Finally, the chapter provides examples of the types of queries that have benefited from the changes made to the Query Optimizer.

The Graphical Plan Viewer and the new set options to display the tree are discussed in Chapter 10.


Queries used for OLTP (online transaction processing) ...

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