I had to help a friend, who's doing their history PhD, design a database for their research. I don't quite know what for. I also directed him to some online SQL

I had to help a friend, who's doing their history PhD, design a database for their research. I don't quite know what for. I also directed him to some online SQL courses. There's also this website https://programminghistorian.org/ https://programminghistorian.org/