Quick tip post. If you have set your data in MySQL to be utf-8 and have special characters such as umlauts (ö) and accents (é) then ensure you add the following:
This could be added to your connection information as follows:
$mysqli = new mysqli($hostname, $username, $password, $database); mysqli_set_charset($mysqli, "utf8");
This sets the character set used in the msqli method to utf8. If this isn't done then data containing some special characters will be returned as null.