protected function prepareTotalCount()
{
if (!$this->query instanceof QueryInterface) {
throw new InvalidConfigException('The "query" property must be an instance of a class that implements the QueryInterface e.g. yii\\db\\Query or its subclasses.');
}
$query = clone $this->query;
return (int) $query->limit(-1)->offset(-1)->orderBy([])->count('*', $this->db);
}