MySQL 直接儲存二進位檔案 (圖片/HTML) 實戰：BLOB 欄位、表單上傳與輸出顯示

資料庫結構設計

CREATE DATABASE binary_data;
USE binary_data;

CREATE TABLE binary_data (
    id INT(4) NOT NULL AUTO_INCREMENT PRIMARY KEY,
    description CHAR(50),
    bin_data LONGBLOB,
    filename CHAR(50),
    filesize CHAR(50),
    filetype CHAR(50)
) ENGINE=InnoDB;

• LONGBLOB：最大 4GB，適合圖片、文件、HTML 等二進位內容。
• 記錄檔名、大小、MIME 類型，便於下載時設定正確 Header。

上傳存儲腳本 store.php

<?php
// store.php
if (isset($_POST['submit'])) {
    $conn = mysqli_connect("localhost", "root", "password", "binary_data");
    $data = addslashes(file_get_contents($_FILES['form_data']['tmp_name']));
    $sql = "INSERT INTO binary_data (description, bin_data, filename, filesize, filetype)
            VALUES ('{$_POST['form_description']}', '$data', '{$_FILES['form_data']['name']}', 
                    '{$_FILES['form_data']['size']}', '{$_FILES['form_data']['type']}')";
    mysqli_query($conn, $sql);
    $id = mysqli_insert_id($conn);
    echo "檔案已存儲，Database ID: $id";
    mysqli_close($conn);
} else {
?>

    檔案描述: 

    
    選擇檔案: 

    

<?php
// getdata.php?id=3
$id = (int)$_GET['id'];
$conn = mysqli_connect("localhost", "root", "password", "binary_data");
$sql = "SELECT bin_data, filetype FROM binary_data WHERE id=$id";
$result = mysqli_query($conn, $sql);
$row = mysqli_fetch_assoc($result);
header("Content-Type: {$row['filetype']}");
echo $row['bin_data'];
mysqli_close($conn);

<img src="getdata.php?id=3" alt="資料庫圖片">
<a href="getdata.php?id=5">下載文件</a>