sql / asp

I have the following SQL query. Query 1 is working fine.
and I tried to modify to get particular rownumber like query 2.
it alerts me error in sql server.

Can experts help me to fix query 2 and tell me what's wrong?
I used this query for website, like asp

Thanks


Query 1:
Select PartNo,
            Row_Number() Over(Order By PartNo) rownumber,
           Count(*) Over() as TotalRecordCount
From Products
where Category = 'COOLANT'
Order By partno asc

Query 2:
Select PartNo,
            Row_Number() Over(Order By PartNo) as  rownumber,
           Count(*) Over() as TotalRecordCount
From Products
where Category = 'COOLANT' and rownumber = 1
Order By partno asc