Question

我试图显示添加的图片的最后“日期”，与特定人有关。

如果我在下面输入一个额外的元素 ORDER BY：，timestamp DESC结果没有变化。同我得到第一张照片的日期。

有些人有一个图像，有些人有五个或更多。数据库中约有1500人。

正确返回所有其他数据/图像。

我在网上找不到任何关于我的问题的参考，更多的概括。

由于

输出结果为： -

Person's - Person -  Nos Of - Last Picture 
Picture     Name    Pictures     "Date"
--------   ------   --------  ------------

image       Tony       5      26th June 2012

image       Beth       1      6th January 2011

image       John       2      5th May 2012

msql_query是： -

<?php

   function person($person_id) {

      $persons = array();

      $persons_query = mysql_query("
         SELECT `persons`.`person_id`, `persons`.`person_name`, 
         LEFT(`persons`.`person_description`, 50) as `person_description`, 
         `person_images`.`timestamp`, `person_images`.`image_person_id`, 
         `person_images`.`person_name`, `person_images`.`ext`, 
          COUNT(`person_images`.`image_person_id`) as `image_count`
          FROM `persons`
          LEFT JOIN `person_images`
          ON `persons`.`person_id` = `person_images`.`person_id`
         LEFT JOIN `person_images`
         ON `persons`.`person_id` = `person_images`.`person_id`
         WHERE `persons`.`member_id` = ".$_SESSION['member_id]
         GROUP BY `persons`.`person_id`
         ORDER BY `persons`.`person_name`, 
     ");

     While ($persons_row = mysql_fetch_assoc($persons_query)) {

        $persons[] = array(
            'person_id'              => $persons_row['person_id'],
           'person_name'            => $persons_row['person_name'],
           'person_description'     => $persons_row['person_description'],
           'timestamp'               => $persons_row['timestamp'],
           'image_person_id'         => $persons_row['image_person_id'],
           'ext'                     => $persons_row['ext'],
           'count'                   => $persons_row['image_count']
        );
     }
     return $persons;
   }
?>

Answer 1

我认为您的问题与订购无关，因为您只对最新图片的日期感兴趣。那你怎么试试呢：

MAX(timestamp) GROUP BY person_id

如何使用多个“ORDER BY”“分组”

1 个答案: