I came to know about this few weeks back and I've also registered. May I also suggest a track (Block) on the basics of Database.
Actually, Block 5, lesson 9: Databases is designed to be just that. What are they, why we need them, the different engines options what's SQL and few other tricks.
Much later, in Block 10, we'll learn about using an ORM but I really feel it's important to understand the theory behind databases before being able to use an ORM :-)