DataTables warning: table id=table_clients - Invalid JSON response. code example

Example: DataTables warning: table id=example-dt - Invalid JSON response.

Plain text12345678910$(document).ready(function () {   $('#example').DataTable({           "processing": true,           "serverSide": true,           ajax: {               url: "/../../admin/server-side-data.php",               type: "GET"           }       });   });