with
t1 as(
    select
        vip,
        sum(order_price) as psum
    from
        order_tb right join uservip_tb using(user_id)
    group by
        vip
)
,t2 as(
    select
        vip,
        (
            case
                when psum is null then 0
                else psum
            end
        ) as order_total
    from
        t1
    order by
        order_total desc
)

select * from t2