private static function erase_notification_data( $student ) {

		$messages = array();
		global $wpdb;
		$deleted = $wpdb->query(
			$wpdb->prepare(
				"DELETE FROM {$wpdb->prefix}lifterlms_notifications WHERE user_id = %d OR subscriber = %d",
				$student->get( 'id' ),
				$student->get( 'id' )
			)
		);

		if ( $deleted ) {

			// Translators: %d = number of notifications.
			$messages[] = sprintf( __( 'Removed %d notifications.', 'lifterlms' ), $deleted );

		}

		return apply_filters( 'llms_privacy_erase_notification_data', $messages, $student );

	}