I've completed it, but I think I'll have to listen to it again later. V1, V2, V3 are definitely noticeable even at the toy project level, but V4, V5, V6 will only be noticeable when you have actual practical experience and have no choice but to use it. In my opinion, if you're seeing it for the first time or are a newbie/junior, listen to Section 4 V3.1, and if there's anything you don't understand, refer to the ORM basics or a book to completely understand it, and if you have to optimize performance by directly querying with DTO while experiencing the actual work, you can come back. And... I guess I'll have to tear down and fix all the toy project codes in progress. ㅋㅋ ㅠ Thank you for the quality lecture.