mysql如何存储文件怎么打开

CREATE TABLE files (
    id INT AUTO_INCREMENT PRIMARY KEY,
    filename VARCHAR(255),
    file_data LONGBLOB
);

<?php
$servername = "localhost";
$username = "username";
$password = "password";
$dbname = "database_name";

// 创建连接
$conn = new mysqli($servername, $username, $password, $dbname);

// 检查连接
if ($conn->connect_error) {
    die("连接失败: " . $conn->connect_error);
}

// 读取文件内容
$file_path = 'example.txt';
$file_data = file_get_contents($file_path);

// 插入数据
$sql = "INSERT INTO files (filename, file_data) VALUES (?, ?)";
$stmt = $conn->prepare($sql);
$stmt->bind_param("ss", $file_path, $file_data);
$stmt->execute();

echo "文件已成功存储";

$stmt->close();
$conn->close();
?>

<?php
$servername = "localhost";
$username = "username";
$password = "password";
$dbname = "database_name";

// 创建连接
$conn = new mysqli($servername, $username, $password, $dbname);

// 检查连接
if ($conn->connect_error) {
    die("连接失败: " . $conn->connect_error);
}

// 检索文件
$sql = "SELECT file_data FROM files WHERE id = ?";
$stmt = $conn->prepare($sql);
$stmt->bind_param("i", $file_id); // 假设你已经知道文件的ID
$stmt->execute();
$stmt->bind_result($file_data);
$stmt->fetch();

// 设置正确的文件头
header('Content-Type: application/octet-stream');
header('Content-Disposition: attachment; filename="example.txt"');

// 输出文件内容
echo $file_data;

$stmt->close();
$conn->close();
?>