SQL Server 2005 introduces the notion of a window, which is a user-specified selection of rows that divides a result set into partitions.You can use these partitions to perform certain calculations in relation to the current row. The current row might be a summary row or contain row-ranking values. For this reason, there are two groups of functions that you can apply to windows: aggregate window functions and ranking window functions.You can use these new window functions in business intelligenc...