row_number vs. rank
I find it hard to fully understand the uniqueness of each function.
If I understand correctly they don't work as same as in different db's.
Moreover, the only difference between them in Vertica is in rank when the order by is the same so the function will give the same number.
That is the only difference?
If so, what will be the equivalent for row_number and rank in SQL SERVER for example in Vertica?
Are there any "Cost" differences, or optimization wise between the two?