Message: mysqli_real_escape_string() expects parameter 1 to be mysqli, boolean given

i got the message

Code:

Severity: Warning

Message: mysqli_real_escape_string() expects parameter 1 to be mysqli, boolean given

Filename: mysqli/mysqli_driver.php

Line Number: 316

im connect to 3 different database with different server too

PHP Code:

$active_group = 'default';
$active_record = TRUE;

$db['default']['hostname'] = 'localhost';
$db['default']['username'] = 'root';
$db['default']['password'] = '';
$db['default']['database'] = 'app';
$db['default']['dbdriver'] = 'mysqli';
$db['default']['dbprefix'] = '';
$db['default']['pconnect'] = TRUE;
$db['default']['db_debug'] = TRUE;
$db['default']['cache_on'] = FALSE;
$db['default']['cachedir'] = '';
$db['default']['char_set'] = 'utf8';
$db['default']['dbcollat'] = 'utf8_general_ci';
$db['default']['swap_pre'] = '';
$db['default']['autoinit'] = TRUE;
$db['default']['stricton'] = FALSE;

/* Dota Statistic Database Configuration */

$db['stats']['hostname'] = '49.128.182.xxx';
$db['stats']['username'] = 'xxx';
$db['stats']['password'] = 'xxx';
$db['stats']['database'] = 'anonstats';
$db['stats']['dbdriver'] = 'mysqli';
$db['stats']['dbprefix'] = '';
$db['stats']['pconnect'] = FALSE;
$db['stats']['db_debug'] = FALSE;
$db['stats']['cache_on'] = TRUE;
$db['stats']['cachedir'] = '';
$db['stats']['char_set'] = 'utf8';
$db['stats']['dbcollat'] = 'utf8_general_ci';
$db['stats']['swap_pre'] = '';
$db['stats']['autoinit'] = FALSE;
$db['stats']['stricton'] = FALSE;

/* PvPGN Database Configuration */

$db['pvpgn']['hostname'] = '49.128.182.xxx';
$db['pvpgn']['username'] = 'xxx';
$db['pvpgn']['password'] = 'xxx';
$db['pvpgn']['database'] = 'pvpgn';
$db['pvpgn']['dbdriver'] = 'mysqli';
$db['pvpgn']['dbprefix'] = '';
$db['pvpgn']['pconnect'] = TRUE;
$db['pvpgn']['db_debug'] = FALSE;
$db['pvpgn']['cache_on'] = FALSE;
$db['pvpgn']['cachedir'] = '';
$db['pvpgn']['char_set'] = 'utf8';
$db['pvpgn']['dbcollat'] = 'utf8_general_ci';
$db['pvpgn']['swap_pre'] = '';
$db['pvpgn']['autoinit'] = FALSE;
$db['pvpgn']['stricton'] = FALSE; 


im try to call model function username_exist

PHP Code:

class Pvpgn extends CI_Model {

    private $pvpgn;
    private $app;

    public function __construct()
    {
        parent::__construct();
        $this->pvpgn = $this->load->database('pvpgn',TRUE);
        $this->app = $this->load->database('default',TRUE);
    }

    public function username_exist($username)
    {
        $this->app->select('id');
        $this->app->where('username', $username);
        $query = $this->app->get('member');

        if ($query->num_rows() == 1) {
            return true;
        } else {
            $this->pvpgn->select('uid');
            $this->pvpgn->where('acct_username', $username);
            $qry = $this->pvpgn->get('pvpgn_BNET');

            if ($qry->num_rows() == 1) {;
                return true;
            } else {
                return false;
            }
        }
    }