Are there any common mistakes or pitfalls to avoid when working with PHP code like this?

One common mistake to avoid when working with PHP code is not properly sanitizing user input, which can lead to security vulnerabilities such as SQL injection attacks. To solve this issue, always use prepared statements or parameterized queries when interacting with a database to prevent malicious input from being executed as SQL commands. 

// Incorrect way of querying the database without sanitizing user input
$user_input = $_POST['username'];
$query = "SELECT * FROM users WHERE username = '$user_input'";
$result = mysqli_query($connection, $query);

// Correct way of using prepared statements to sanitize user input
$user_input = $_POST['username'];
$stmt = $connection->prepare("SELECT * FROM users WHERE username = ?");
$stmt->bind_param("s", $user_input);
$stmt->execute();
$result = $stmt->get_result();

Keywords

syntax errors undefined variables SQL injection XSS attacks infinite loops

Related Questions