Chapter Objectives
In this chapter you will learn:
n The objectives of query processing and optimization.
n Static versus dynamic query optimization.
n How a query is decomposed and semantically analyzed.
n How to create a relational algebra tree to represent a query.
n The rules of equivalence for the relational algebra operations.
n How to apply heuristic transformation rules to improve the efficiency of a query.
n The types of database statistics required to estimate the cost of operations.
n The different strategies for implementing the relational algebra operations.
n How to evaluate the cost and size of the relational algebra operations.
n How pipelining can be used to improve the efficiency of queries.
n The difference between materialization and pipelining.
n The advantages of left-deep trees.
n Approaches for finding the optimal execution strategy.
n How Oracle handles query optimization.