Vlad Mihalcea’s work stands out because it is not academic. It is pragmatic. For every pattern (e.g., "Use a DTO projection"), there is a counter-pattern (e.g., "Avoid DTO projections for graph of objects") with specific benchmarks to prove the point.
This executes a single SQL update statement, bypassing the Persistence Context entirely and saving massive overhead. High-performance Java Persistence.pdf