bgruver,
Teradata has Rank function which will help u get the top n values. something like this
select
sub.city_desc,
sub.sales_value,
rank(sub.sales_value)
from
(
select
city_desc as city_desc,
sum(sales_value) as sales_value
from
city_sales
group by
city_desc
)as sub
qualify rank(sales_value) <= 5
the above sql will get u the top 5 cities based on sales value.
Regards,
Sridharan