I guess it depends on the region. E.g in China QR codes (and similar codes) were widely used more than 10 years ago by hundreds of millions of people on a daily basis for payments, ordering at restaurants, apps sharing or social media.

What languages/framework are you going to use it with? I would bet you'll thank yourself for switching to Postgres instead of MySQL at some point. Have you read www.amazingcto.com/postgres-for... ? :)