My SQL Alter function error

Question

This is MySql code Alter Function

DELIMITER $$
ALTER FUNCTION Tepat(tgl_permohonan DATETIME, total_hari_kerja INT)
    RETURNS INT WITH EXECUTE AS CALL AS BEGIN
    DECLARE jumlah_hari INT, i INT, selisih INT;
    SET i = 0;
    SET jumlah_hari = 0;
    WHILE (i < total_hari_kerja) 
    BEGIN 
    IF (EXTRACT(WEEK FROM tgl_permohonan) != 6) AND (EXTRACT(WEEK FROM tgl_permohonan) != 5)
    BEGIN
        SET i = i + 1;
    END IF;
    SET jumlah_hari = jumlah_hari + 1;
    SET tgl_permohonan = DATE_ADD(tgl_permohonan, INTERVAL 1 DAY);
    END;
    SET selisih = DATEDIFF(tgl_permohonan, NOW());
    IF selisih <= 0
    BEGIN
    SET selisih = 0;
    END IF;
    RETURN selisih;
    END; $$
DELIMITER ;

getting the following error:

1064 - You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near '(tgl_permohonan DATETIME, total_hari_kerja INT) RETURNS INT WITH EXECUTE AS CALL AS BEGIN' at line 1

Answer 1

In order to change a stored function in MySQL you have to drop and recreate it.

DROP FUNCTION Tepat;
CREATE FUNCTION Tepat(...

ALTER FUNCTION only let you change the characteristics (like COMMENT or DEFINER) of a function.

ALTER FUNCTION Syntax
This statement can be used to change the characteristics of a stored function. More than one change may be specified in an ALTER FUNCTION statement. However, you cannot change the parameters or body of a stored function using this statement; to make such changes, you must drop and re-create the function using DROP FUNCTION and CREATE FUNCTION.