Row_Number Returns the sequential number of a row within a partition of a result set, starting at 1 for the first row in each partition.ROW_NUMBER ( ) OVER ([] )Rank Returns the rank of each row within the partition of a result set. The rank of a row is one plus the number of ranks that come before the row in question.RANK ( ) OVER ([< partition_by_clause >] < order_by_clause >)