var fredNameRef = new Firebase('https://docs-examples.firebaseio.com/samplechat/users/fred/name');

fredNameRef.on('value', function(snap) {
  console.log(snap.val());
});

fredNameRef.update({ first: 'Wilma', last: 'Flintstone' });



credit: https://stackoverflow.com/questions/36105690/how-to-return-success-data-after-update-in-firebase