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The Basics of SQL Query Code Tuning
The chapter begins Part II of this book, which focuses on aspects of Ora-
cle SQL code provided specifically for tuning of data–warehouse type
functionality. In order to introduce aspects of tuning SQL code for data
warehouses, it is necessary to go back to basics. This chapter will provide
three things: (1) details of the most simplistic aspects of SQL code tun-
ing, (2) a description of how the Oracle SQL engine executes SQL code
internally, and (3) a brief look at tools for tuning Oracle Database. It is
essential to understand the basic facts about how to write properly per-
forming SQL code and perform basic ...