php - 使用 php 进行 mysqli 数据库备份

Question

当 mysql 工作时，我使用此代码来获取数据库的备份:

if (isset($_POST['getbackup'])) { 

    $db = "newsite";
    $version = "2.3.1";
    $date = date('Y-m-d H:i:s');

    $final = "--   #".$version."#\n";
    $final .= "--   database backup\n";
    $final .= "--\n";
    $final .= "--   PHP version: ".phpversion()."\n";
    $final .= "--   MySQL version: ".mysqli_get_server_info($mysqli)."\n";
    $final .= "--   Date: ".date("r")."\n";

    $result = $mysqli->query("SHOW TABLE STATUS FROM ".$db);
    while ($table = $result->fetch_array()) {
    $i = 0;
    $result2 = $mysqli->query("SHOW COLUMNS FROM $table[0]");
    $z = $result2->num_rows;
    $final .= "\n--\n-- DB Export - Table structure for table `".$table[0]."`\n--\n\nCREATE TABLE `".$table[0]."` (";
    $prikey = false;
    $insert_keys = null;
    while ($row2 = $result2->fetch_array()) {
        $i++;
        $insert_keys .="`".$row2['Field']."`";
        $final .= "`".$row2['Field']."` ".$row2['Type'];
        if($row2['Null'] != "YES") { $final .= " NOT NULL"; }
        if($row2['Default']) $final .= " DEFAULT '".$row2['Default']."'";
        if($row2['Extra']) { $final .= " ".$row2['Extra']; }
        if($row2['Key'] == "PRI") { $final .= ", PRIMARY KEY  (`".$row2['Field']."`)"; $prikey = true; }
        if($i < $z){
            $final .= ", ";
            $insert_keys .=", ";
        }
        else{
            $final .= " ";
        }
    }
    if($prikey) {
        if($table[10]) $auto_inc = " AUTO_INCREMENT=".$table[10];
        else $auto_inc = " AUTO_INCREMENT=1";
    }
    else $auto_inc = "";
    $charset = explode("_", $table[14]);
    $final .= ") ENGINE=".$table[1]." DEFAULT CHARSET=".$charset[0]." COLLATE=".$table[14].$auto_inc.";\n\n--\n-- DB Export - Dumping data for table `".$table[0]."`\n--\n";

    $inhaltq = $mysqli->query("SELECT * FROM $table[0]");
    while($inhalt = $inhaltq->fetch_array()) {
        $final .= "\nINSERT INTO `$table[0]` (";
        $final .= $insert_keys;
        $final .= ") VALUES (";
        for($i=0;$i<$z;$i++) {

            $inhalt[$i] = str_replace("'","`", $inhalt[$i]);
            $inhalt[$i] = str_replace("\\","\\\\", $inhalt[$i]);
            $einschub = "'".$inhalt[$i]."'";
            $final .= preg_replace('/\r\n|\r|\n/', '\r\n', $einschub);
            if(($i+1)<$z) $final .= ", ";

        }
        $final .= ");";
    }
    $final .= "\n";
}
if($logged) {
    header("Expires: 0");
    header("Cache-Control: must-revalidate, post-check=0, pre-check=0");
    header("Content-Type: application/force-download");
    header("Content-Description: File Transfer");
    if(is_integer(mb_strpos(strtolower($_SERVER["HTTP_USER_AGENT"]), "msie")) AND is_integer(mb_strpos(strtolower($_SERVER["HTTP_USER_AGENT"]), "win" ))) header("Content-Disposition: filename=backup-".strtolower(date("D-d-M-Y")).".sql;");
    else header("Content-Disposition: attachment; filename=backup-".strtolower(date("D-d-M-Y")).".sql;");
    header("Content-Transfer-Encoding: binary");
}

}

现在也可以了，当我单击按钮时，我会下载一个文件，但该文件中没有 SQL 文件，而是页面的源代码在文件中。

我做错了什么？

Answer 1

您没有输出 $final 数据。我正在使用这段代码做完全相同的事情，尝试一下......

header('Content-Description: File Transfer');
header('Content-type: application/octet-stream');
header('Content-Disposition: attachment; filename=' . $backup_filename . '.sql');
header('Content-Transfer-Encoding: binary');
header('Content-Length: ' . strlen($final));
header('Cache-Control: must-revalidate, post-check=0, pre-check=0');
header('Expires: 0');
header('Pragma: public');
echo $final;