SPs in MySql can hurt, big-time. This book is actually very helpful in that it describes query/table/schema tuning techniques that're useful regardless of whether or not your sql is in an SP. It's also very useful in that it lets you know all that can be done with SPs, Functions, and Triggers in MySql. What it doesn't tell you: depending on your SP query, server config, and how often you call the SP, you may not want to implement that MySql feature as you'll blow out your server memory. So it's exciting to see what can be done in MySql as of version 5, and this book brings those features to life. But make sure you test everything as there were definitely some bugs in the 5.0 release that, depending on your db, won't let you implement everything you read about here.