public static void main(String[] args) throws Exception	{		SimpleDateFormat sdf=new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");//		long timeStart=sdf.parse("2011-09-20 12:30:45").getTime();		long timeStart=1492775948000L;		System.out.println(timeStart);		Date date = new Date(timeStart);		System.out.println(sdf.format(date));				//		//2017-05-12 22:11:25//		String ss = "2017-05-12 22:11:25";//		long l=sdf.parse(ss).getTime();//		System.out.println(l);//1494598285000//		//		long timeStart2=1494598285000L;//		Date date2 = new Date(timeStart2);//		System.out.println(sdf.format(date2));				//yyyy-MM-dd HH:mm:ss.SSS//    	1494059400 000//    	2017-05-06 16:30:00//    	1494059460 000//    	2017-05-06 16:31:00    	//60000   ms		//60 s				//SELECT m.*,((now()-m.createTime)/1000) as time,SYSDATE() as sysdate, (SYSDATE()-date_format('2017-05-13 14:38:00', '%Y%m%d%H%i%s')) as test FROM tbl_hbb_resource_video_info r,tbl_hbb_mobile_live_info m where r.resourceId=m.resourceId and m.startTime is null and ((now()-m.createTime)>0) and r.STATUS = '1'        //SELECT m.*,((now()-m.createTime)/1000) as time,SYSDATE() as sysdate, (SYSDATE()-date_format('2017-05-12 22:11:25', '%Y%m%d%H%i%s')) as test FROM tbl_hbb_resource_video_info r,tbl_hbb_mobile_live_info m where r.resourceId=m.resourceId and m.startTime is null and ((now()-m.createTime)>0) and r.STATUS = '1'	}

SELECT m.*,((now()-m.createTime)/1000) as time,SYSDATE() as sysdate, (SYSDATE()-date_format('2017-05-13 14:38:00', '%Y%m%d%H%i%s')) as test FROM tbl_hbb_resource_video_info r,tbl_hbb_mobile_live_info m where r.resourceId=m.resourceId and m.startTime is null and ((now()-m.createTime)>0) and r.STATUS = '1'SELECT m.*,((now()-m.createTime)/1000) as time,SYSDATE() as sysdate, (SYSDATE()-date_format('2017-05-12 22:11:25', '%Y%m%d%H%i%s')) as test FROM tbl_hbb_resource_video_info r,tbl_hbb_mobile_live_info m where r.resourceId=m.resourceId and m.startTime is null and ((now()-m.createTime)>0) and r.STATUS = '1'select timestampdiff(hour,'2008-08-08 12:00:00','2008-08-08 00:00:00'); -- -12select timestampdiff(hour,'2008-08-08 00:05:00','2008-08-08 00:00:00'); -- 0select timestampdiff(minute,'2008-08-08 00:05:30','2008-08-08 00:00:00'); -- 5select timestampdiff(second,'2008-08-08 00:05:00','2008-08-08 00:00:00'); -- 300SELECT m.*,((now()-m.createTime)/1000) as time,SYSDATE() as sysdate,timestampdiff(second,SYSDATE(),m.createTime) as ss, (SYSDATE()-date_format('2017-05-12 22:11:25', '%Y%m%d%H%i%s')) as test FROM tbl_hbb_resource_video_info r,tbl_hbb_mobile_live_info m where r.resourceId=m.resourceId and m.startTime is null and ((now()-m.createTime)>0) and r.STATUS = '1'

注意：

(SYSDATE()-date_format('2017-05-12 22:11:25', '%Y%m%d%H%i%s')) 

是按照 每一位去 减的

例如

当前时间是 2017-05-13 13:40:25

(SYSDATE()-date_format('2017-05-13 13:38:00', '%Y%m%d%H%i%s'))

计算出来是  225  其实 是 分钟 和 秒数  分别减的，   2   、 25