In WordPress there is the `$wpdb` class, that abstracts database access away. It is advised to use `$wpdb->prepare()` with prepared statements. Then you have an

In WordPress there is the `$wpdb` class, that abstracts database access away. It is advised to use `$wpdb->prepare()` with prepared statements. Then you have an array with placeholders and an array with values, which the `$wpdb` class should handle correctly. But looking at this code, simply casting to an int with `(int) $id` in the `set_id()` method would have been enough.