


How to Display the Last 5 Uploaded Images from a MySQL Database in a Gallery Format?
Displaying BLOB Images from MySQL Database
Introduction:
MySQL is a commonly used relational database management system that allows for the storage of various data types, including binary large objects (BLOBs). BLOBs are useful for storing images, audio files, or other binary data. This article aims to guide you through displaying the last 5 images uploaded to a MySQL database in a gallery-like format.
Querying for the Last 5 Images:
To retrieve the last 5 images from the database, you'll need to execute the following SQL query:
SELECT image FROM table_name ORDER BY id DESC LIMIT 5;
This query selects the image column from the specified table_name, orders the results in descending order by the id column (assuming it's the unique identifier for each image), and limits the results to the last 5 rows.
Fetching and Displaying the Images:
After executing the query, you'll use a while loop to fetch the results and display the images:
<code class="php">$result = mysqli_query($db, $sql); while ($row = mysqli_fetch_array($result)) { echo "<img src="php/imgView.php?imgId=%22%20.%20%24row%5B" image . alt="How to Display the Last 5 Uploaded Images from a MySQL Database in a Gallery Format?" >"; }</code>
- mysqli_query() executes the SQL query and returns the result set.
- mysqli_fetch_array() retrieves the next row of data from the result set.
- The while loop continues until there are no more rows left in the result set.
- For each row, the image is displayed using an HTML image tag.
imgView.php File:
The imgView.php file is responsible for retrieving the image data from the database and outputting it as an image:
<code class="php"><?php $id = addslashes($_REQUEST['imgId']); $image = mysqli_query($db, "SELECT image FROM table_name WHERE id=$id"); $image = mysqli_fetch_assoc($image); $image = $image['image']; header("Content-type: image/jpeg"); echo $image; ?></code>
- addslashes() escapes special characters in the imgId parameter.
- mysqli_query() executes the SQL query to retrieve the image data.
- mysqli_fetch_assoc() retrieves the result as an associative array.
- header() sets the Content-Type header to specify that the output is an image.
- echo $image outputs the retrieved image data as an image.
Integration with Your Code:
To integrate this functionality into your existing code, you can:
- Replace the gallery.php file with the code provided above.
- Ensure that the imgView.php file is accessible in the correct path.
- Use the sql variable and execute it using mysqli_query($db, $sql).
By following these steps, you can display the last 5 uploaded images in a MySQL database as a gallery-style interface.
The above is the detailed content of How to Display the Last 5 Uploaded Images from a MySQL Database in a Gallery Format?. For more information, please follow other related articles on the PHP Chinese website!

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