function __construct($db_prefix, $dsn, $username = "", $password = "", $driver_options = null)
{
global $server_dir;
if (self::$pdo_instance === null) {
self::$pdo_instance = new PDO($dsn, $username, $password, $driver_options);
}
$sql_type = substr($dsn, 0, strpos($dsn, ':'));
$path = $server_dir . '/core/driver/' . $sql_type . '.php';
if (!file_exists($path)) {
throw new ErrorNotFound("Driver " . $sql_type . " not found with path: {$path}");
}
include_once $path;
$this->sql_instance = new $sql_type();
$this->db_prefix = $db_prefix;
}
