The introductory course was very thorough. Before listening to this, I had also listened to other lecturers' lectures, and I learned that the technology I learned there was Spring Data JPA through this introductory course. I am ashamed of myself in the past for thinking that JPA was nothing special. It was a valuable time to draw a big picture, and I have also purchased JPA Utilization 1 and JPA Introduction, so I will start studying right away. Thank you for the great lecture. Younghan.