One more "real-world" caveat: there could be a tie for the number 25 spot, so simply using "Top 25" in the select may leave a worthy salesperson off the list. One way to include all who belong would be to use the RANK() function. I like to wrap such in a CTE, but a correlated sub-query or other structure may be just as sound (or better) for your use.

Declare @StartDt Datetime

Declare @EndDt Datetime

Set @StartDt = '20090101'

Set @EndDt = '20090131'

;with

Sales (SalesRank, SalesPerson, TotSalesDollars)

as

(Select SalesRank = Rank() over (order by sum(SalesDollars) Desc)

,SalesPerson

,sum(SalesDollars)

from #SalesTbl

Where SalesDate between @StartDt and @EndDt

group by SalesPerson) --end of CTE

selectSalesRank

,SalesPerson

,TotSalesDollars

from Sales

where SalesRank <= 25