Write Inside Loop (ARCH4052)

Key java.orm.write-inside-loop · Severity error · Category orm

Calling save/flush on every loop iteration produces a separate DB round-trip per record. Accumulate the writes and flush once outside the loop.

Incorrect

for (User user : users) {
    user.setActive(true);
    userRepository.save(user); // flush each iteration -> N round-trips
}

Correct

for (User user : users) {
    user.setActive(true);
}
userRepository.saveAll(users); // single batch

Fix

Move the persist call out of the loop and apply it once via saveAll/batch flush.