English to Russian Tech/Engineering IT (Information Technology) Microsoft SQL Server

The thing with the ROW_NUMBER function—and window functions in general—is that
they are only allowed in the SELECT and ORDER BY clauses of a query. So, what if you want to
filter rows based on such a function’s result? For example, suppose you want to return only
the rows where the row number is less than or equal to 2; namely, in each category, you want
to return the two products with the lowest unit prices, with the product ID used as a tiebreaker.