MYSQL regarding Foreign Keys

So, after my initial colorful consternation, I was totally prepared to rail on about this question (because I got it wrong, lol). But then, after finding a couple sources that reaffirmed my consternation, I went and clicked the link to the documentation, and *poof* delusions of grandeur gone and pitchfork back in the shed.

This is why these questions are useful. I'd consider my MySQL knowledge to be pretty solid, but I was solidly mistaken on this one! Kudos, braindigitalis!

I didn't find the right solution from the Internet.
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