sjs-tutorial-xquery-eval.sjs

/*
 * Evaluate standard XPath against JSON (or XML or both). JSON properties operate similar to unnamespaced
 * XML elements.
 */
var total = 0, count = 0;
// XPath is a subset of XQuery. Evaluate it.
var resultIter = 
  xdmp.xqueryEval('/node()[some $name in friends/name satisfies starts-with(upper-case($name), "N") or eyeColor = "blue"]');
for (var result of resultIter) {
  total += result.age;
  count++;
};
"Average age of people who have blue eyes or are friends with others whose names start with \"N\": " + (total/count);