First time for me to review a book on Sensual, but I just finished MySQL Database Design and Tuning by Robert D. Schneider (MySQL Press, ISBN 0-672-32765-1), and considered it to be both a good read and am sure it will prove a good reference in the future. For the most part, the author is straight to the point providing realistic scenarios and solutions. He also covers a plethora of variables that affect database performance, and exactly how to monitor certain aspects to determine which settings to adjust.
His primary focus is on MyISAM and InnoDB, as they are the most popular, but he does have a brief chapter at the end of the book covering NDB (Clustering). Overall, it was worth the read, so if you’re struggling with database performance, or just feel like getting more into the database administration side of MySQL, pick up a copy =)