from_unixtime('1436926771','%Y-%m-%d %H:%i:%s') 结果: 2015-07-15 10:19:31
date_format('2008-08-08 22:23:01', '%Y%m%d%H%i%s')
str_to_date('08/09/2008', '%m/%d/%Y'); -- 2008-08-09
unix_timestamp('2008-08-08 12:30:00'); -- 1218169800
from_unixtime(1218169800); -- '2008-08-08 12:30:00'
date_add('2008-08-08 12:00:00', interval -8 hour); -- 2008-08-08 04:00:00