This post(https://blog.scudata.com/a-major-culprit-in-the-slow-running...) explains why java-based SPL can run much faster than the C++-based database. BTW, SPL also support columnar storage, it can implement columnar storage in a single file. And here is a test report https://blog.scudata.com/spl-computing-performance-test-seri.... It sounds amazing, but it is not mysterious. A lot of low complexity algorithms can not be implemented in SQL, programmer can only expect the optimizer of database. howerver ,when SQL is complex, optimizer would get lost.