I took about half of the class. Overall, the lecture quality itself is not bad. If I had to compare, it would be the style of a school professor. I am taking a database class at school, so I took this class to prepare for the exam, and it is enough for the exam. But there is a downside. The person above said that it is okay to follow the class with MYSQL, but in my personal opinion, It seems a little difficult. Of course, the concept itself is similar. For example, there is no SELECT INTO in MYSQL. However, there is a part in the class that teaches SELECT INTO. And because it is so grammatically different, WORKBENCH keeps saying that it is an incorrect SQL grammar. The class is 15~20 minutes long, but if you Google it for 10~15 minutes, you will get really angry. Please refer to it.