public function add($data)
{
if (count($this->_values) && $data instanceof Query || $this->_query && is_array($data)) {
throw new Exception('You cannot mix subqueries and array data in inserts.');
}
if ($data instanceof Query) {
$this->query($data);
return;
}
$this->_values[] = $data;
$this->_castedExpressions = false;
}