Php Memcache&；Mysqli准备语句问题

检查下面的代码，我有以下问题：SQL语句中的最后两个参数是动态的，我如何使memcache获得正确的参数，而不仅仅是？，哪个只给我看？添加第二个变量$sql1=“从tpost ORDER按id desc LIMIT$var1，$var2选择id title vtext”？还是给出了更好的解决方案

$sql = "SELECT id, title, vtext FROM tpost ORDER BY id desc LIMIT ?, ?";
$content = $memcache->get($sql);

if($content == null) {
    $stmt = $mysqli->prepare($sql);
    $stmt->bind_param('ii', $offset, $rowsperpage);
    $stmt->execute();
    $stmt->bind_result($r_id, $r_title, $r_vtext); 
    while ($stmt->fetch()) {
        $data[] = array( 'id' => $r_id, 'title' => $r_title, 'vtext' => $r_vtext);
    }
    $stmt->close(); 

    $memcache->set($sql,$data,0,$cache_time);

}

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感谢您的帮助

使用完整的SQL查询作为密钥是不好的做法。创建唯一标识符或至少对其进行哈希运算。原因是，当您的密钥越大，匹配速度越慢，数据传输速度越慢（使用小密钥到memcache服务器的1000r/s比使用大密钥的1000r/s快：）

$sql = "SELECT id, title, vtext FROM tpost ORDER BY id desc LIMIT ?, ?";
$key = "SELECT id, title, vtext FROM tpost ORDER BY id desc LIMIT $r_title, $r_vtext";
$content = $memcache->get($sql);

if($content == null) {
 $stmt = $mysqli->prepare($sql);
 $stmt->bind_param('ii', $offset, $rowsperpage);
 $stmt->execute();
 $stmt->bind_result($r_id, $r_title, $r_vtext); 
 while ($stmt->fetch()) {
    $data[] = array( 'id' => $r_id, 'title' => $r_title, 'vtext' => $r_vtext);
 }
 $stmt->close(); 

 $memcache->set($key,$data,0,$cache_time);

}

数据也可以是空的，如果用户请求超出范围，只检查它并再次进入SQL查询是不明智的

            // Generate key
    $key = 'recent:'. $offset .':'. $rowsperpage;

    // If nothing found within cache instance, retrieve and set it
    if(!$data = $memcache->get($key)) {
        $sql = "SELECT `id`, `title`, `vtext` 
                 FROM `tpost` 
             ORDER BY `id` DESC LIMIT ?, ?";

        $stmt = $this->$mysqli->prepare($sql);
        $stmt->bind_param('ii', $offset, $rowsperpage);

        // Retrieve result set
        if($stmt->execute()) {
            $data = array();
            $stmt->bind_result($r_id, $r_title, $r_vtext); 
            while ($stmt->fetch()) {
                $data[] = array(
                                'id' => $r_id,
                                'title' => $r_title,
                                'vtext' => $r_vtext);
            }
        }

        $stmt->close(); 

        // Set cache entry
        $memcache->set($key, $data, 0, $cache_time);