Oracle DB Connection with Query

DbClass.php

<?php
class Db {
    public $url = 'http://localhost/DashboardObject/';
    protected $host = '192.--.--.54';
    protected $SID = 'qpro';
    protected $userName = 'brac_central_db';
    protected $password = '123456';
    protected $port = '1521';
    protected $db;
    public function __construct(){
        $this->db = oci_connect($this->userName, $this->password, $this->host.'/'.$this->SID);
        if (!$this->db) {
            $e = oci_error();
            trigger_error(htmlentities($e['message'], ENT_QUOTES), E_USER_ERROR);
        }
    }

    public function query($query){
        $query = oci_parse($this->db, $query);
        oci_execute($query);
        $nrows = oci_fetch_all($query, $res, null, null, OCI_FETCHSTATEMENT_BY_ROW);
        return $res;

    }
}

Great boss..