mysql 的时间格式

UPDATE item SET DATETIME= DATE_FORMAT('2012-07-15 16:28:58','%Y-%m-%d %H:%i:%s')

SELECT * FROM item WHERE DATETIME>NOW()

SELECT FROM_UNIXTIME( 1340985540, '%Y%m%d %H%i%s' )  ;

SELECT UNIX_TIMESTAMP('2012-06-29 23:59:00') ;