In PHP, what are the implications of including line breaks or special characters in database entries, and how can they be properly sanitized for storage?

Including line breaks or special characters in database entries can lead to SQL injection attacks or unintended behavior when querying the database. To properly sanitize input before storing it in the database, you can use functions like mysqli_real_escape_string() to escape special characters and prevent SQL injection.

// Assuming $conn is your database connection
$input = "Input with line breaks or special characters";
$sanitized_input = mysqli_real_escape_string($conn, $input);

// Now $sanitized_input can be safely stored in the database