select top(1) with ties s.Name
, sum(isnull(o.Amount, 0)) as Quantity
from Sellers as s
inner join Orders as o
on s.id = o.Salesperson_id
where o.Order_date is not null and o.Order_date > '20091231'
group by s.id's.Name
having count(o.Salesperson_id) > 1
order by sum(isnull(o.Amount, 0)) desc
, row_number() over(partition by s.id order by (select null))
select s.Name
, sum(nvl(o.Amount, 0)) as Quantity
from Sellers as s
Orders as o
where's.id = o.Salesperson_id
and o.Order_date is not null
and o.Order_date > to_date('20091231','YYYYMMDD') /*if this is a date*/
group by s.id's.Name
having count(o.Salesperson_id) > 1
order by sum(nvl(o.Amount, 0)) desc
offset 0 rows fetch next 1 rows only
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