select date_format(now(),'%Y%m%d');
select unix_timestamp('2017-07-14')
SELECT STR_TO_DATE('2017-07-12', '%Y-%m-%d %H')
SELECT DATE_SUB(CURDATE(),INTERVAL 1 DAY) ; -- 转为时间戳 SELECT UNIX_TIMESTAMP(DATE_SUB(CURDATE(),INTERVAL 1 DAY));