ms sql row_number over partition
USE AdventureWorks2012;
GO
SELECT FirstName, LastName, TerritoryName, ROUND(SalesYTD,2,1) AS SalesYTD,
ROW_NUMBER() OVER(PARTITION BY TerritoryName ORDER BY SalesYTD DESC)
AS Row
FROM Sales.vSalesPerson
WHERE TerritoryName IS NOT NULL AND SalesYTD <> 0
ORDER BY TerritoryName;