CSCTbyHs

1update `visitors_stats` set avg_visit_duration=if(avg_visit_duration=0,41371,round((avg_visit_duration*(visitors_number-1)+41371)/visitors_number,2)) , max_visit_duration= if(41371>max_visit_duration,41371,max_visit_duration) , min_visit_duration = if(min_visit_duration=0,41371,if(41371<min_visit_duration,41371,min_visit_duration)) where memberid="74e57e4027c250edc9f1c4d38136d935" and `date`="2016-10-27"
2	
3CREATE TABLE IF NOT EXISTS `visitors_stats` (
4  `id` int(11) NOT NULL AUTO_INCREMENT,
5  `memberid` varchar(32) NOT NULL,
6  `date` date NOT NULL,
7  `visitors_number` int(6) NOT NULL DEFAULT '0',
8  `avg_visit_duration` double NOT NULL DEFAULT '0',
9  `max_visit_duration` double NOT NULL DEFAULT '0',
10  `min_visit_duration` double NOT NULL DEFAULT '0'
11  PRIMARY KEY (`id`),
12  UNIQUE KEY `date` (`date`,`memberid`)
13) ENGINE=InnoDB  DEFAULT CHARSET=utf8;