CREATE FUNCTION `mathToChar`(`str` INT) RETURNS VARCHAR(100) character set gbk
BEGIN 
DECLARE str1 VARCHAR(1) character set gbk DEFAULT  '' ; 
    DECLARE return_str VARCHAR(255) character set gbk DEFAULT '' ; 
    DECLARE i INT DEFAULT 1; 
    WHILE i < CHAR_LENGTH(str) + 1  DO 
     SET str1 = SUBSTRING(str,i,1);         
    CASE str1 
    WHEN '1' THEN SET str1 ="一"; 
    WHEN '2' THEN SET str1 ="二"; 
    WHEN '3' THEN SET str1 ="三"; 
    WHEN '4' THEN SET str1 ="四"; 
    WHEN '5' THEN SET str1 ="五"; 
    WHEN '6' THEN SET str1 ="六"; 
    WHEN '7' THEN SET str1 ="七"; 
    WHEN '8' THEN SET str1 ="八"; 
    WHEN '9' THEN SET str1 ="九"; 
	WHEN '0' THEN SET str1 ="零";
    END CASE;         
        SET return_str = CONCAT(return_str,str1); 
        SET i = i + 1 ; 
	END WHILE; 
    RETURN return_str; 
END;
SELECT mathToChar(213123) AS mathTochar;
 

建立自定義函式，測試。