Oracle provides several options to aid performance, such as partitioning large tables, using materialized views, storing plan outlines, and many others. This chapter examines how DBAs can use these techniques to aid developers’ efforts to increase the efficiency of their application code. This chapter introduces the SQL Tuning Advisor to help you tune SQL statements. You can then use the recommendations of this advisor to rewrite poorly performing SQL code. I begin the chapter with a discussion of how to approach performance tuning. More than the specific performance improvement techniques you use, your approach to performance tuning determines your success in tuning a recalcitrant application system.