This code sample is adapted from Clifford B. Anderson and Joseph C. Wicentowski, XQuery for Humanists (College Station: Texas A&M University Press, 2020), 217. Download this code sample in its raw form. View the source on GitHub.

xquery version "3.1";

let $book := fn:doc("book.xml")
return
    insert node <genre>Science Fiction</genre> into $book/book