2

my table structure was like 

CREATE TABLE `survey` (
  `id` int(11) NOT NULL auto_increment,
  `submitdate` datetime default NULL,
 `answer` varchar(5) collate utf8_unicode_ci default NULL,
  PRIMARY KEY  (`id`)
) ENGINE=MyISAM  DEFAULT CHARSET=utf8 COLLATE=utf8_unicode_ci AUTO_INCREMENT=499 ;

Now I want to calculate last 10 days records. Suppose no record on particular day. it should be zero.

the output is like 

date         count
19-11-2012   10
18-11-2012   30 
13-11-2012   0 
      .
      .

i have used query like 

SELECT COUNT( * ) , DATE( submitdate ) 
FROM survey t
WHERE t.submitdate >= ( CURDATE( ) - INTERVAL 10 
DAY ) 
GROUP BY DATE( submitdate ) 
LIMIT 0 , 30

output is 

count(*)    date(submitdate)
1   2012-11-13
2   2012-11-14
1   2012-11-15
3   2012-11-16
6   2012-11-17

not giving 0 for no records with dates.

4

2 回答 2

8

你可以尝试这样的事情来获得输出： -

 SELECT * FROM survey t WHERE t.date >= DATE_ADD(CURDATE(), INTERVAL -10 DAY);

或者你可以试试这个： -

 SELECT * FROM survey t WHERE t.date >= ( CURDATE() - INTERVAL 10 DAY )

检查Date_Add文档

于 2012-11-18T18:29:34.327 回答
7

这就是你需要的：

SELECT days.day, count(survey.id)
FROM
  (select curdate() as day
   union select curdate() - interval 1 day
   union select curdate() - interval 2 day
   union select curdate() - interval 3 day
   union select curdate() - interval 4 day
   union select curdate() - interval 5 day
   union select curdate() - interval 6 day
   union select curdate() - interval 7 day
   union select curdate() - interval 8 day
   union select curdate() - interval 9 day) days
  left join survey
   on days.day = survey.submitdate
group by
  days.day

（如果 submitdate 包含日期和时间，则应将该行替换on days.day = survey.submitdate为on days.day = DATE(survey.submitdate)）

于 2012-11-18T18:46:31.947 回答