phpcms左侧栏目数据统计错误

$sql = "SELECT * FROM `v9_category` WHERE `parentid` = 0";
$result = $db->query($sql);
while ($row = $db->fetch_array($result)) {
    // 处理数据
}

phpcms_cache_clear();

function get_left_menu() {
    $sql = "SELECT * FROM `v9_category` WHERE `parentid` = 0";
    $result = $db->query($sql);
    $menu = array();
    while ($row = $db->fetch_array($result)) {
        $menu[$row['catid']] = $row;
        $children = get_children($row['catid']);
        if (!empty($children)) {
            $menu[$row['catid']]['children'] = $children;
        }
    }
    return $menu;
}

function get_children($parentid) {
    $sql = "SELECT * FROM `v9_category` WHERE `parentid` = $parentid";
    $result = $db->query($sql);
    $children = array();
    while ($row = $db->fetch_array($result)) {
        $children[$row['catid']] = $row;
        $grandchildren = get_children($row['catid']);
        if (!empty($grandchildren)) {
            $children[$row['catid']]['children'] = $grandchildren;
        }
    }
    return $children;
}