Found in 3 comments on Hacker News
neallindsay · 2017-01-17 · Original thread
I recommend Database Design for Mere Mortals https://www.amazon.com/Database-Design-Mere-Mortals-Hands-eb...
edw519 · 2010-06-13 · Original thread
I always thought that "Database Design for Mere Mortals: A Hands-On Guide to Relational Database Design" by Michael J. Hernandez was a great starting point. Sometimes it's nice to have a real book and you can't go wrong with a used one from Amazon for under 5 bucks.

http://www.amazon.com/Database-Design-Mere-Mortals-Hands/dp/...

Fresh book recommendations delivered straight to your inbox every Thursday.