Not PHP specific (as others have mentioned, "advanced" MySQL knowledge should be language-independent), but here you go (from this question and this question):
Understanding MySQL Internals :
Learn how data structures and convenience functions operate, how to add new storage engines and configuration options, and much more
High Performance MySQL:
Learn how to design schemas, indexes, queries and advanced MySQL features for maximum performance, and get detailed guidance for tuning your MySQL server, operating system, and hardware to their fullest potential. You'll also learn practical, safe, high-performance ways to scale your applications with replication, load balancing, high availability, and failover.
Pro MySQL:
Topics include transaction processing and indexing theory, benchmarking and profiling, and advanced coverage of storage engines, data types, subqueries, derived tables, and joins. Also covers MySQL 5's new enterprise features like stored procedures, triggers, and views.
(partial descriptions from Amazon included, see respective product page for more detailed info).