What best practices should be followed when designing a PHP application that involves user interaction with database records and navigation between pages?

When designing a PHP application that involves user interaction with database records and navigation between pages, it is important to follow best practices to ensure security, efficiency, and maintainability. Use prepared statements to prevent SQL injection attacks, validate user input to prevent malicious data entry, and implement proper error handling to provide a seamless user experience. Additionally, consider implementing a clean and organized folder structure for your PHP files and use sessions to maintain user state across different pages.

// Sample code snippet demonstrating the use of prepared statements to interact with a database in a secure manner

// Establish a database connection
$pdo = new PDO('mysql:host=localhost;dbname=mydatabase', 'username', 'password');

// Prepare a SQL statement using a prepared statement
$stmt = $pdo->prepare("SELECT * FROM users WHERE username = :username");
$stmt->bindParam(':username', $_POST['username']);
$stmt->execute();

// Fetch the results
$user = $stmt->fetch(PDO::FETCH_ASSOC);

// Display the user information
echo "Username: " . $user['username'] . "<br>";
echo "Email: " . $user['email'];