how to fetch data from js file using ajax code example

Example: how to fetch data from database in javascript using ajax

var xhttp = new XMLHttpRequest();
  xhttp.onreadystatechange = function() {
    if (this.readyState == 4 && this.status == 200) {
      return this.responseText;
    }
  };
  xhttp.open("GET", "[your database]", true);
  xhttp.send();


//add the url of your database in the [your database] string.