select  DATE_SUB(CURDATE(), INTERVAL 6 DAY) ;

SELECT
    date_add(
    date_sub( ( SELECT DATE_SUB( curdate( ), INTERVAL 6 DAY ) ), INTERVAL 1 DAY ),
    INTERVAL ( cast( help_topic_id AS signed ) + 1 ) DAY 
    ) dayStr 
FROM
    mysql.help_topic 
WHERE
    help_topic_id < DATEDIFF( NOW( ), date_sub( ( SELECT DATE_SUB( curdate( ), INTERVAL 6
 
 DAY ) ), INTERVAL 1 DAY ) ) 
ORDER BY
    help_topic_id ;


SELECT DATE_FORMAT(CURDATE(), '%Y-%m') month FROM DUAL
        UNION ALL SELECT DATE_FORMAT(date_sub(CURDATE(), INTERVAL 1 MONTH), '%Y-%m') month FROM DUAL
        UNION ALL SELECT DATE_FORMAT(date_sub(CURDATE(), INTERVAL 2 MONTH), '%Y-%m'
 
) month FROM DUAL
        UNION ALL SELECT DATE_FORMAT(date_sub(CURDATE(), INTERVAL 3 MONTH), '%Y-%m') month FROM DUAL
        UNION ALL SELECT DATE_FORMAT(date_sub(CURDATE(), INTERVAL 4 MONTH), '%Y-%m') month FROM DUAL
        UNION ALL SELECT DATE_FORMAT(date_sub(CURDATE(), INTERVAL 5 MONTH), '%Y-%m
 
') month FROM DUAL;

SELECT @s :=@s + 1 as 'index', DATE(DATE_SUB(CURRENT_DATE, INTERVAL @s DAY)) AS 'date' FROM mysql.help_topic,(SELECT @s := 0) temp WHERE @s < 7 ORDER BY 'date' ;