Grant all procedures that were changed TODAY (or other date as parameter) in any database (as parameter) for any user (as parameter). Works for MariaDB too.

grants_on_all_procedures_and_functions_mysql.sql

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-- Creates procedure that takes schema/user/modificationFromDate as parameters and calls it for some schema/user/today in the end. This works for MariaDB too.

-- Example of grant as concat select
-- SELECT CONCAT('GRANT EXECUTE ON PROCEDURE YOUR_SCHEMA.', routine_name, ' TO user@`10.1.%`;') FROM information_schema.routines where routine_schema = 'YOUR_SCHEMA'  AND ROUTINE_TYPE = 'PROCEDURE';
-- SELECT CONCAT('GRANT EXECUTE ON FUNCTION YOUR_SCHEMA.', routine_name, ' TO user@`10.1.%`;') FROM information_schema.routines where routine_schema = 'YOUR_SCHEMA' AND ROUTINE_TYPE = 'FUNCTION';

---- Grant all procedures that were changed TODAY (or other date as parameter) in any database (as parameter) for any user (as parameter)
DROP PROCEDURE IF EXISTS SysExecuteGrantsForModifiedProcedures;
CREATE PROCEDURE SysExecuteGrantsForModifiedProcedures(IN p_schema VARCHAR(120), IN p_mysqlUser VARCHAR(120),
                                                       IN p_fromModificationDate DATETIME)
BEGIN
    DECLARE v_done INT DEFAULT FALSE;
    DECLARE v_statement TEXT;
    # Get all the modified procedures/functions
    DECLARE cur1 CURSOR FOR SELECT CONCAT('GRANT EXECUTE ON PROCEDURE `', ROUTINE_SCHEMA, '`.`', routine_name, '` TO ',
                                          p_mysqlUser, ';')
                            FROM information_schema.routines
                            where routine_schema = p_schema
                              AND ROUTINE_TYPE = 'PROCEDURE'
                              AND date(LAST_ALTERED) >= date(p_fromModificationDate)
                            UNION
                            SELECT CONCAT('GRANT EXECUTE ON FUNCTION `', ROUTINE_SCHEMA, '`.`', routine_name, '` TO ',
                                          p_mysqlUser, ';')
                            FROM information_schema.routines
                            where routine_schema = p_schema
                              AND ROUTINE_TYPE = 'FUNCTION'
                              AND date(LAST_ALTERED) >= date(p_fromModificationDate);

    DECLARE CONTINUE HANDLER FOR NOT FOUND SET v_done = TRUE;

    SET max_sp_recursion_depth = 1024;

    OPEN cur1;

    read_loop:
    LOOP
        FETCH cur1 INTO v_statement;
        IF v_done THEN
            LEAVE read_loop;
        END IF;
        PREPARE stmt FROM v_statement;
        EXECUTE stmt;
        DEALLOCATE PREPARE stmt;
    END LOOP;

    CLOSE cur1;

end;

-- And execute the procedure
CALL SysExecuteGrantsForModifiedProcedures('YOUR_SCHEMA', 'user@`10.1.%`', NOW());
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