1, junior high school culture "want to learn SQL database to become an engineer" is very difficult, and most people can't do it.

2. Being a related engineer is not just about learning SQL database.

3. Related to SQL database is "programming". There are so few things that simple SQL can do that it can hardly be applied to practical work. The function of SQL is only to manipulate the data in the database, just like the warehouse administrator can do.

4. There are few separate SQL databases for amateur class teaching, for the same reason as "3", and there are few "programmers" for amateur class teaching, because it is very difficult and needs systematic learning.

Of course, if you are interested, you can teach yourself slowly, or you can consider enrolling in a professional full-time class.