After graduating, I started self-teaching myself SQL using Codecademy and books. I've listed this on my resume in a way that implies I'm not very experienced with the language but am familiar with it. I'd like a way to show employers my SQL skills more directly.
Standard advice to show employers your skills is to create projects or portfolios. Here's where my problem lies: I have no idea what the format is for these. Considering that I'm dealing SQL, I can't just build a website or app to show what I know. I'm assuming that projects in a portfolio involve more than just a document of plain code. Or is that all there is to it?