Oing! I am writing a review for the first time. It was a satisfying lecture because I was able to continuously improve my SQL skills and learn about service indicators. While solving the problems, I thought that the instructor had put a lot of thought into creating the problems. The difficulty level was well organized for each session, and the instructor set a good time limit, so I was able to have fun solving the problems. In particular, in the last session, I could feel my skills improving as I watched myself writing criteria step by step and freely executing subqueries. In the last lecture, there was a part called GAU in the comments, and when I searched, I found out that GAU is also a service indicator in the game industry. In addition to the content, during the problem-solving time, the instructor taught me how to solve each problem thoroughly and also showed me other solutions, so I was able to develop the ability to write query statements from a new perspective. If the instructor opens an intermediate lecture in the future, I will definitely listen to it. Thank you for creating a great lecture.