Paul reviewed High performance MySQL by Baron Schwartz
Review of 'High performance MySQL' on 'Goodreads'
4 stars
Some excellent tips in here, particularly the sections on table types and indexes. More of a reference work that you'll dip into than something to read from cover to cover - e.g. I keep a printed copy of the explanation of EXPLAIN columns on my desk.
If you have the electronic version from O'Reilly, make sure you download the latest copy as there was a second release in 2015.