How can PHP developers effectively troubleshoot and debug issues related to image uploads and database interactions in their scripts?

Issue: When troubleshooting image uploads and database interactions in PHP scripts, developers can use error handling techniques to identify and resolve issues more effectively. By using functions like `error_reporting()` and `ini_set()`, developers can display errors, warnings, and notices that may occur during image uploads and database interactions. Additionally, developers can check for specific error messages, validate input data, and use debugging tools like `var_dump()` or `print_r()` to inspect variables and data structures. 

// Enable error reporting for debugging
error_reporting(E_ALL);
ini_set('display_errors', 1);

// Example image upload code
if(isset($_FILES['image'])){
    $file_name = $_FILES['image']['name'];
    $file_tmp = $_FILES['image']['tmp_name'];
    
    // Check for errors during upload
    if($_FILES['image']['error'] !== UPLOAD_ERR_OK){
        echo "Error during file upload.";
    } else {
        // Move uploaded file to desired directory
        move_uploaded_file($file_tmp, "uploads/".$file_name);
        echo "File uploaded successfully.";
    }
}

// Example database interaction code
$connection = mysqli_connect("localhost", "username", "password", "database");

// Check for connection errors
if(mysqli_connect_errno()){
    echo "Failed to connect to MySQL: " . mysqli_connect_error();
}

// Query database
$query = "SELECT * FROM table";
$result = mysqli_query($connection, $query);

// Check for query errors
if(!$result){
    echo "Error executing query: " . mysqli_error($connection);
} else {
    // Process query results
    while($row = mysqli_fetch_assoc($result)){
        echo $row['column_name'];
    }
}

// Close database connection
mysqli_close($connection);

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