Let's put this in ... a database ^_^!
Far be it from me to stop you, but making conventional databases available over the Internet is a hard problem from a practical configuration point of view. Directly exposing a database server is dangerous, and providing a safe front-end that's easily usable is no small matter. In addition, support for SQL temporal facilities is limited, so recovering from a bad change would be hard. I suppose people could checkout a SQLite database from git, but then there would have to be an informal pessimistic lock of some kind.
Google Sheets, on the other hand, is fairly secure, user-friendly, concurrent, historical, your data is backed up by a commercial enterprise (we lost a lot of R6RS history because the trusted person serving it up dropped off the net and there were no backups), and even has a SQLish language in the QUERY function, though it cannot join.