ORDER BY LATEST

Question

我不知道PHP编码，我有一个使用PHP作为后端服务与JSON的Android应用程序。它会取出最后添加的最新图像，但是对于类别图像，它会随机显示。我正在尝试对类别图像进行排序，并将其作为最后添加的图像必须先排序，如果您是专家，请帮助我解决难题。

我对获取的图像API是像下面

<?php 
include ("includes/connection.php"); 
include ("purchase.php"); 
if (purchase_status() == false) { 
    echo "<p>Sorry, we are unable to verify your purchase.</p>"; 
    exit ; 
} else { 
    if (isset($_GET['cat_id'])) { 
     $cat_id = $_GET['cat_id']; 
     $cat_img_res = mysql_query('SELECT * FROM tbl_category WHERE cid=\'' . $cat_id . '\''); 
     $cat_img_row = mysql_fetch_assoc($cat_img_res); 
     $cid = $cat_img_row['cid']; 
     $cat_nm = $cat_img_row['category_name']; 
     $files = array(); 
     $dir = opendir(dirname(realpath(__FILE__)) . '/categories/' . $cat_img_row['category_name'] . '/'); 
     while ($file = readdir($dir)) { 
      if ($file == '.' || $file == '..') { 
       continue; 
      } 
      $allimages[] = $file; 
     } 
     $total_arr = array_merge((array)$cat_nm, (array)$allimages); 
     sort($total_arr); 
     foreach ($total_arr as $key => $file) { 

      if ($key != count($total_arr) - 1) { 
       $array['HDwallpaper'][] = array('images' => $file, 'cat_name' => $cat_nm, 'cid' => $cid); 
      } 
     } 
     echo stripslashes(json_encode($array)); 
    } else if (isset($_GET['latest'])) { 
     $limit = $_GET['latest']; 
     $query = "SELECT tbl_gallery.image,tbl_category.category_name FROM tbl_gallery 
      LEFT JOIN tbl_category ON tbl_gallery.cat_id= tbl_category.cid 
      ORDER BY tbl_gallery.id DESC LIMIT $limit"; 
     $resouter = mysql_query($query); 
     $set = array(); 
     $total_records = mysql_numrows($resouter); 
     if ($total_records >= 1) { 
      while ($link = mysql_fetch_array($resouter, MYSQL_ASSOC)) { 
       $set['HDwallpaper'][] = $link; 
      } 
     } 
     echo $val = str_replace('\\/', '/', json_encode($set)); 
    } else { 
     $query = "SELECT cid,category_name,category_image FROM tbl_category"; 
     $resouter = mysql_query($query); 
     $set = array(); 
     $total_records = mysql_numrows($resouter); 
     if ($total_records >= 1) { 
      while ($link = mysql_fetch_array($resouter, MYSQL_ASSOC)) { 
       $set['HDwallpaper'][] = $link; 
      } 
     } 
     echo $val = str_replace('\\/', '/', json_encode($set)); 
    } 
} 
?> 

Answer 1

只是用户在PHP MySQL查询如下：

mysql_query("SELECT * FROM tbl_category WHERE cid='".$cat_id."' ORDER BY cid DESC"); 

如果您有存储上传数据的时间，那么这是完美的获取最新上传图像的方法如下：

mysql_query("SELECT * FROM tbl_category WHERE cid='".$cat_id."' ORDER BY uploaded_time DESC");