Any suggestion for a comprehensive and advanced SQL course?

Question

As the title implies, I wanted to ask whether you guys have any recommendation for an advanced SQL course. If possible, a free course that can prepare to polish one's SQL skillset for a data scientist career. I've checked edX but I thought it would be more prudent to ask for others' opinions rather than exploring through all of the courses. Your opinion would be greatly appreciated.

Answer 1

You can find the advanced SQL course on www.w3schools.com