This book makes a number of references to APT scripts. APT stands for Advanced Performance Tuning. It is merely my personal toolkit of Oracle performance tuning scripts. The scripts referred to in this book can be obtained from O’Reilly’s web site or from my own (see “Comments and Questions”). APT is not a commercial product, and I do not warrant that the scripts are error-free. But you are free to use them, or glean from them what you may.