select 
  t1.id,
  is_group_buy,
  client_name
from 
  (
  select
    o.id,
    is_group_buy,
    name as client_name,
    count(*) over(partition by user_id) as cnt 
  from 
    order_info as o
  left join 
    client as c 
  on 
    o.client_id=c.id
  where 
    date>'2025-10-15' and product_name in ('C++','Python','Java') and status='completed'
  ) as t1
where
  cnt>=2
order by 
  t1.id;