PHP: Fatal error: Class 'BackendlessDataQuery' not found

I tried the sample:


$contact = new Contact();$query = new BackendlessDataQuery(); $query->setWhereClause('age = 147');     $result_collection = Backendless::$Persistence->of( 'Contact’ )->find( $query );

It does not work. Error “Fatal error: Class ‘BackendlessDataQuery’ not found”

Hi!

try to add line

<?php
use backendless\Backendless;
use backendless\services\persistence\BackendlessDataQuery;

Thank you. Ok now.