Found in 3 comments on Hacker News
neallindsay · 2017-01-17 · Original thread
I recommend Database Design for Mere Mortals
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.

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