private function create()
{
$this->write_magic_time('created_at');
$this->write_magic_time('updated_at');
$pk = $this->primary_key();
$table = $this->table();
$fields = $this->map_real_fields();
$sql_fields = implode("`,`", array_keys($fields));
$sql_values = implode(",", array_map(array($this, 'prepare_for_value'), $fields));
$sql = "INSERT INTO `{$table}` (`{$sql_fields}`) VALUES ({$sql_values});";
DbCommand::execute($sql);
$this->{$pk} = DbCommand::insert_id();
$this->_exists = true;
}
