mysql 金额转大写函数

DELIMITER $$

CREATE FUNCTION `num_to_cn`(num DECIMAL(15,2)) RETURNS VARCHAR(255) CHARSET utf8
BEGIN
    DECLARE units VARCHAR(10) DEFAULT '拾佰仟万拾佰仟亿拾佰仟';
    DECLARE nums VARCHAR(10) DEFAULT '零壹贰叁肆伍陆柒捌玖';
    DECLARE result VARCHAR(255) DEFAULT '';
    DECLARE num_str VARCHAR(15) DEFAULT LPAD(FLOOR(num), 15, '0');
    DECLARE len INT DEFAULT LENGTH(num_str);
    DECLARE i INT DEFAULT 1;
    
    WHILE i <= len DO
        SET result = CONCAT(result, SUBSTRING(nums, SUBSTRING_INDEX(SUBSTRING_INDEX(units, ',', i), ',', -1) + 1, 1), SUBSTRING(num_str, len - i + 1, 1));
        SET i = i + 1;
    END WHILE;
    
    -- 处理多余的零
    SET result = REPLACE(result, '零零', '零');
    SET result = REPLACE(result, '零拾', '拾');
    SET result = REPLACE(result, '零佰', '佰');
    SET result = REPLACE(result, '零仟', '仟');
    SET result = REPLACE(result, '零万', '万');
    SET result = REPLACE(result, '零亿', '亿');
    SET result = REPLACE(result, '亿万', '亿');
    
    -- 处理单位
    SET result = CONCAT(SUBSTRING(result, 1, 1), '元', SUBSTRING(result, 2));
    
    RETURN result;
END$$

DELIMITER ;

SELECT num_to_cn(123456789.12); -- 输出：壹亿贰仟叁佰肆拾伍万陆仟柒佰捌拾玖元壹角贰分