//first initialize firebase
//to sync data when object changes
//this code block takes a snapshot from database and 'console.log' it
//create database reference
const dbRef = firebase.databse.ref().child('childName');
//taking snapshot
dbRefObject.on('value', snap => console.log(snap.val()));
//if you want to parse data to charts (chart.js, hightcharts.js) please refer their docs too.