Mysql function to remove non-alphanumeric character from a string

delimiter // DROP FUNCTION IF EXISTS remove_non_alphanum_char_f // CREATE FUNCTION remove_non_alphanum_char_f (prm_strInput varchar(255)) RETURNS VARCHAR(255) DETERMINISTIC BEGIN  DECLARE i INT DEFAULT 1;  DECLARE v_char VARCHAR(1);  DECLARE v_parseStr VARCHAR(5000) DEFAULT ' '; WHILE (i <= LENGTH(prm_strInput) ) DO  SET v_char = SUBSTR(prm_strInput,i,1);  IF v_char REGEXP '^[A-Za-z0-9 ]+$' THEN #alphanumeric  SET v_parseStr = CONCAT(v_parseStr,v_char); END IF;  SET i = i + 1; END WHILE; RETURN trim(v_parseStr); END //