php - 使用 MySQL INTO OUTFILE 不写入 tmp

Question

我最近将一个项目移动到实时 VM 实例，它在我的 macOS 机器上使用 XAMPP 进行开发和测试期间运行完美。本质上，网络应用程序有 3 个导出选项:XML、PDF 和 CSV。 XML 工作正常，它是使用 SELECT 语句创建的，然后循环遍历结果并将其推送到 XML 文件中。

但是对于 CSV 和 PDF 导出(PDF 使用 TCPDF)我使用了:

CSV

INTO OUTFILE '/tmp/$department_name+feedback+$timestamp.csv' FIELDS TERMINATED BY ',' LINES TERMINATED BY '\n'";

PDF

INTO OUTFILE '/tmp/$department_name+feedback+$timestamp.txt' FIELDS TERMINATED BY ';' LINES TERMINATED BY '\n'";

但是文件永远不会写入/tmp。我认为这是一个权限问题，但是该目录归 root 所有，并且具有预期的所有必要权限。

工作的XML代码如下:

$fileLocation = '/tmp/' . $location_name . '+feedback+' . $timestamp . '+.xml';

$sql = "SELECT CONCAT (e.name,' ', e.surname) AS Fullname, f.score AS Score, d.department_name AS Department, f.feedback AS Feedback
            FROM employee AS e
            JOIN feedback AS f
            ON e.qr_id = f.qr_id
            JOIN departments as d
            ON e.department_id = d.department_id
            JOIN location AS l
            ON e.location_id = l.location_id
            AND e.location_id = '$location'
            AND e.company_id = '$company_id'
            AND f.`report_Time` BETWEEN SUBDATE(CURDATE(),
                                INTERVAL 1 MONTH) AND NOW()
                                ORDER BY f.score DESC";


$xml = new XMLWriter();

$xml->openURI($fileLocation);
$xml->startDocument();
$xml->setIndent(true);

$xml->startElement('feedback');

foreach ($mysqli->query($sql) as $row){
    $xml->startElement("Fullname");
    $xml->writeRaw($row['Fullname']);
    $xml->startElement("Score");
    $xml->writeRaw($row['Score']);
    $xml->startElement("Feedback");
    $xml->writeRaw($row['Feedback']);
    $xml->startElement("Department");
    $xml->writeRaw($row['Department']);

    $xml->endElement();
}

$xml->endElement();

header('Content-type: text/xml');
$xml->flush();


$file_url = $fileLocation;
header('Content-Type: application/xml');
header("Content-Transfer-Encoding: Binary");
header("Content-disposition: attachment; filename=\"" . basename($file_url) . "\"");
readfile($file_url);

所以我不确定为什么 XML 在写入/tmp 目录时有效，而 PDF 和 CSV 却没有，这是在 Google Cloud Platform VM 实例上运行的。正如我之前所说，CSV 和 PDF 导出在我的 macOS 机器上运行良好。

Answer 1

显示结果:

SHOW VARIABLES LIKE 'secure_file_priv';

如果Result不为NULL只能在该目录下写入。