Mysql取得当日、昨日、先週、今週、先月、今月の時間

当日:

SELECT DATE_FORMAT(CURDATE(),'%Y-%m-%d 00:00:00')
SELECT DATE_FORMAT(CURDATE(),'%Y-%m-%d 23:59:59')

昨日:

SELECT DATE_FORMAT(DATE_SUB(CURDATE(), INTERVAL 1 DAY), '%Y-%m-%d 00:00:00')
SELECT DATE_FORMAT(DATE_SUB(CURDATE(), INTERVAL 1 DAY), '%Y-%m-%d 23:59:59')

先週:

SELECT DATE_FORMAT(DATE_SUB(DATE_SUB(CURDATE(),INTERVAL WEEKDAY(CURDATE()) DAY),INTERVAL 1 WEEK),'%Y-%m-%d 00:00:00')
SELECT DATE_FORMAT(SUBDATE(CURDATE(), WEEKDAY(CURDATE()) + 1), '%Y-%m-%d 23:59:59')

今週:

SELECT DATE_FORMAT( DATE_SUB(CURDATE(), INTERVAL WEEKDAY(CURDATE()) DAY), '%Y-%m-%d 00:00:00')
SELECT DATE_FORMAT( DATE_ADD(SUBDATE(CURDATE(), WEEKDAY(CURDATE())), INTERVAL 6 DAY), '%Y-%m-%d 23:59:59')

先月:

SELECT DATE_FORMAT( DATE_SUB(CURDATE(), INTERVAL 1 MONTH), '%Y-%m-01 00:00:00')
SELECT DATE_FORMAT( LAST_DAY(DATE_SUB(CURDATE(), INTERVAL 1 MONTH)), '%Y-%m-%d 23:59:59')

今月:

SELECT DATE_FORMAT(CURDATE(), '%Y-%m-01 00:00:00')
SELECT DATE_FORMAT(LAST_DAY(CURDATE()), '%Y-%m-%d 23:59:59')

ある月に何日ありますか.
SELECT DAY(LAST_DAY('2018-06-01'));