satori-services/public/recent-registrations.php

<?php
require_once '_flashii.php';

$startId = (int)filter_input(INPUT_GET, 'start', FILTER_SANITIZE_NUMBER_INT);

try {
    $fetch = $db->prepare('
        SELECT `user_id`, `username`
        FROM `msz_users`
        WHERE `user_id` > ?
        AND `user_created` > NOW() - INTERVAL 7 DAY
        ORDER BY `user_id`
        LIMIT 10
    ');
    $fetch->addParameter(1, $startId);
    $fetch->execute();
    $result = $fetch->getResult();

    $sets = [];
    while($result->next())
        $sets[] = [
            'user_id' => $result->getInteger(0),
            'username' => $result->getString(1),
        ];

    echo json_encode($sets);
} catch(Exception $ex) {
    echo json_encode(['error' => 104, 'msg' => $ex->getMessage()]);
}