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说明：核心部分就是代码中时间显示部分代码，2010-09-01 00:00:00 是结束时间，43664 MINUTE 是指统计范围为 2010.9.1 0:00 前30天过7小时44分内，其实就是 2010.8.1 16:16 ～2010.8.31 24:00这个时段啦。

    
     get_results("
         SELECT COUNT(comment_author) AS cnt, comment_author, comment_author_url, comment_author_email
         FROM (SELECT * FROM $wpdb->comments LEFT OUTER JOIN $wpdb->posts
         ON ($wpdb->posts.ID=$wpdb->comments.comment_post_ID)
         WHERE comment_date > date_sub( '2010-09-01 00:00:00', INTERVAL 43664 MINUTE )
         AND user_id='0'
         AND comment_author_email != $my_email
         AND post_password=''
         AND comment_approved='1'
         AND comment_type='') AS tempcmt    GROUP BY comment_author_email
         ORDER BY cnt DESC LIMIT $limit_num
     ");
     foreach ($counts as $count) {
       $c_url = $count->comment_author_url;
       if ($c_url == '') $c_url = $noneurl;
       $mostactive .= '
  • ' . 'comment_author . ' ('. $count->cnt . 'comments)">'.get_avatar($count->comment_author_email,$size='40').'
    • ';
     }
     echo $mostactive;
     ?>

一些例子：

1. 2010.8.18~2010.8.20内的读者墙：date_sub( '2010-08-20 00:00:00', INTERVAL 3 DAY)

2. 最近一周内：date_sub(NOW(), INTERVAL 1 WEEK)

……

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附：SQL 的 date_sub() 函数

DATE_SUB() 函数从日期减去指定的时间间隔。

语法

DATE_SUB(date,INTERVAL expr type)

date 参数是合法的日期表达式；expr 参数是您希望添加的时间间隔。

Type 值

MICROSECOND
SECOND
MINUTE
HOUR
DAY
WEEK
MONTH
QUARTER
YEAR
SECOND_MICROSECOND
MINUTE_MICROSECOND
MINUTE_SECOND
HOUR_MICROSECOND
HOUR_SECOND
HOUR_MINUTE
DAY_MICROSECOND
DAY_SECOND
DAY_MINUTE
DAY_HOUR
YEAR_MONTH

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