DELIMITER //

CREATE FUNCTION make_locale_std_code(parm_language INT(11) UNSIGNED, parm_region INT(11) UNSIGNED) RETURNS int(11) unsigned
    READS SQL DATA
    DETERMINISTIC
BEGIN
	DECLARE result_code varchar(8);
	DECLARE language_iso_code varchar(2);
	DECLARE region_iso_code varchar(2);
	
	SELECT l10n_language.iso_code into language_iso_code
	FROM l10n_language
	WHERE l10n_language.id = parm_language_id;
	
	SELECT l10n_region.iso_code into region_iso_code
	FROM l10n_region
	WHERE l10n_region.id = parm_region_id;
	
	IF 		CHAR_LENGTH(region_iso_code) = 0
	THEN	set result_code = language_iso_code;
	ELSE	set result_code = CONCAT(language_iso_code, '-', region_iso_code);
	END IF;
	
	RETURN result_code;
END
//

DELIMITER ;