This project includes two sql scripts(cmdev.sql, world.sql) to create databases required in the practice.
And a sql script, i.e. mynotes.sql, that includes instantly-runnable commands covering the following topics:

CRUD, join and union, subquery, MySQL datatypes intro, commonly-used functions, and toy-data.

I use mynotes.sql as a detailed reminder, but it can also be used as a tutorial for SQL-beginners.

You can find more SQL practices in the folder "MySQL_Homework" or https://github.com/macdidi5/MySQLTutorial, and also on Leetcode, section "database" https://leetcode.com/problemset/database/

References: http://www.codedata.com.tw/database/mysql-tutorial-getting-started/