Chapter 1. Oracle SQL TuningPocket Reference
This book is a quick-reference guide for tuning Oracle SQL. This is not a comprehensive Oracle tuning book.
The purpose of this book is to give you some light reading material on my “real world” tuning experiences and those of my company, Mark Gurry & Associates. We tune many large Oracle sites. Many of those sites, such as banks, large financial institutions, stock exchanges, and electricity markets, are incredibly sensitive to poor performance.
With more and more emphasis being placed on 24/7 operation, the pressure to make SQL perform in production becomes even more critical. When a new SQL statement is introduced, we have to be absolutely sure that it is going to perform. When a new index is added, we have to be certain that it will not be used inappropriately by existing SQL statements. This book addresses these issues.
Many sites are now utilizing third-party packages such as Peoplesoft, SAP, Oracle Applications, Siebel, Keystone, and others. Tuning SQL for these applications must be done without placing hints on SQL statements, because you are unauthorized to touch the application code. Obviously, for similar reasons, you can’t rewrite the SQL. But don’t lose heart; there are many tips and tricks in this reference that will assist you when tuning packaged software.
This book portrays the message, and my firm belief, that there is always a way of improving your performance to make it acceptable to your users.