I Ignored These JPA Methods for Years-Now Spring Boot Application 10 Faster

"After years of ignoring some key JPA methods and annotations, I finally explored them - and what happened next was shocking: my application became up to 10× faster with fewer queries, less memory use, and way cleaner code. 🎉 If you are not a Medium Member then Click hereto read free. 🔄 1. JpaRepository.existsById() Instead of findById()"

"If you only need to check if something exists: if (userRepository.existsById(id)) { // no need to load entire entity} ✅ Why it's faster: Avoids unnecessary entity loading and reduces SQL size. 💾2. saveAll() - The Implicit Batch Saver For years, I called save() in a loop - like this: for (User user : users) { userRepository.save(user);} But that's inefficient. Instead, use: userRepository.saveAll(users); Hint: saveAll() still calls save() for each entity internally, but the persistence context can optimize batching if you configure it correctly"

Using JpaRepository.existsById() avoids loading full entities when only existence checks are needed, reducing SQL payload and memory use. Replacing repeated save() calls with saveAll() lets the persistence context optimize persistence operations and enables implicit batching when hibernate.jdbc.batch_size is configured. Proper batching consolidates SQL work, lowers the number of queries, reduces memory pressure from the persistence context, and simplifies code. These repository-level changes yield large performance gains and cleaner data-access logic with minimal code changes.

Read at Medium