/**
	 * @param int $code - code id
	 * @param int $newacc - new account id
	 * @param int $oldacc - old account id
	 * @return int|string
	 */
	protected static function tradecode($code, $newacc, $oldacc) {
		$char = char_code::getchar($code);

		if ($char != 0)
			return "Nur nicht Charakter gebundene Codes können getauscht werden.";
		if ($newacc == 0)
			return "Neue Account ID ist Ungültig";

		$sql = 'UPDATE ' . self::getFullTableName() . ' SET account_id = :new, trade_to_id = :new, trade_from_id = :old WHERE code = :code';

		return SQL::execute(self::getConnection(), $sql,
			array(
				"new" => $newacc,
				"old" => $oldacc,
				"code" => $code
			)
		);
	}