Pdo_database.php not workin properly

function &getAssoc($query)
{
$this->verifyQuery($query);
global $globalTime;
logprofile($globalTime, true);
//fixed code
$sth = $this->db->prepare($query);
$sth->execute();
$result = $sth->fetchAll();
//
//bug - pdo can`t find any getAssoc() function, because pdo don`t support it.
$result = &$this->db->getAssoc($query);
logprofile($globalTime, $query);
//bug - in the upper code pdo has defined $this->db = new PDO() and PDO dose not have ady function like isError

/*if(DB::isError($result))
{
$this->error($result);
}*/
//fixed
if($this->db->errorInfo($result))
{
$this->error($result);
}
return $result;
}

I explored the all code of the file there are lot of the same bugs.