My state had a reading competition that listed books by ISBN, which was a real challenge for students to track down. Each library had different editions and even different cover art, so if you “found” the book you might not recognise it on the shelf, etc…

I worked on the library systems and one of my innovations was to use the ISBN mapping database of WorldCat to find books with identical content but different ISBNs to help kids find the books on the list.

Over ten years that one SQL join in the code made the kids read an extra million books they wouldn’t have otherwise.

My biggest “bang for buck” in my career!