javascript - Remove value from database using Cloud Functions

Question

I have the following data structure:

How do I completely remove 'days' using a Cloud Function?

My current code:

const functions = require('firebase-functions');
const admin = require('firebase-admin');
admin.initializeApp(functions.config().firebase);

     exports.deleteOldItems = functions.database.ref('/path/to/items/{pushId}')
    .onWrite(event => {
      var ref = event.data.ref.parent; // reference to the items
      var now = Date.now();
      var cutoff = now - 2 * 60 * 60 * 1000;
      var oldItemsQuery = ref.orderByChild('timestamp').endAt(cutoff);
      return oldItemsQuery.once('value', function(snapshot) {
        // create a map with all children that need to be removed
        var updates = {};
        snapshot.forEach(function(child) {
          updates[child.key] = null
        });
        // execute all updates in one go and return the result to end the function
        return ref.update(updates);
      });

functions.database.ref('/days').remove(); // <- /days doesn't get removed

    });

Answer 1

Waitting for answers