What are common security risks associated with using PHP and MySQL, particularly in relation to SQL injections?

SQL injections are a common security risk when using PHP and MySQL, where attackers can manipulate SQL queries to gain unauthorized access to the database. To prevent SQL injections, it is crucial to use prepared statements or parameterized queries to sanitize user input before executing SQL queries.

// Using prepared statements to prevent SQL injections
$stmt = $pdo->prepare("SELECT * FROM users WHERE username = :username");
$stmt->bindParam(':username', $username);
$stmt->execute();