ALTER {PROCEDURE | FUNCTION} sp_name [characteristic ...]

characteristic:
    { CONTAINS SQL | NO SQL | READS SQL DATA | MODIFIES SQL DATA }
  | SQL SECURITY { DEFINER | INVOKER }
  | COMMENT 'string'

This statement can be used to change the characteristics of a stored routine (that is, a stored procedure or stored function). More than one change may be specified in an ALTER PROCEDURE or ALTER FUNCTION statement. However, you cannot change the parameters or routine body of a stored routine using this statement; to make such changes, you must first drop the routine using DROP PROCEDURE or DROP FUNCTION, then re-create the routine using CREATE PROCEDURE or CREATE FUNCTION.

As of MySQL 5.0.3, you must have the ALTER ROUTINE privilege for the routine. (That privilege is granted automatically to the routine creator.) If binary logging is enabled, this statement might also require the SUPER privilege, as described in Section 17.5, “Binary Logging of Stored Programs”.