Question

我的表结构就像

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 ;

现在我要计算过去4周的记录数。

有一件事是，如果假设某一周没有记录，它应该列为0

这里的示例输出类似于

count(*) week 
  0      mon-sun  //29 oct -  4 nov every week starts from monday and ends with sunday 
  4      mon-sun  //5 nov -  11 nov
  45     mon-sun  //12 nov -  18 nov  last week 
  0      mon-sun  //18 nov - 25 nov  latest week

假设今天是星期一，那么周范围变化到最近一周的星期一。

Answer 1

查询将如下所示：

SELECT
    s.id,
    DATE(DATE_SUB(s.submitdate,INTERVAL(DAYOFWEEK(s.submitdate) - 2) DAY)) AS weekStart,
    ADDTIME(SUBTIME(SUBDATE(s.submitdate,INTERVAL(DAYOFWEEK(s.submitdate) - 8)DAY),TIME(s.submitdate)),MAKETIME(23,59,59)) AS weekEnd,
    COUNT(*) AS total
FROM survey s
GROUP BY weekStart
LIMIT 0,3

我怎么能找到最近4周的记录数？

1 个答案: