Learning SQL in a more structural way

My first encounter with relational databases was when I started building my first Django blog. It began with SQLite and later moved to PostgreSQL. Along the way, I somehow managed to get everything I needed. Later, I worked with Snowflake and YugabyteDB, but never delved deeply into the subject.

After one challenging interview, I decided to organize the bits of knowledge I had. I found this interactive, free SQL course at sqbolt.com, which provides a solid foundation. If you need to quickly start working with SQL queries, I highly recommend giving it a try. 

It covers about 90% of what you’ll need, including all the basic commands, aggregation, subqueries, unions, etc.