Jean-Luc Lachance <jllachan@nsd.ca> writes:
> Is the number of record per page and the number of key per page taken in
> consideration?
Yes, indirectly. (The cost equations actually use total tuples and
total pages in each table/index, but that's isomorphic to using average
tuple size or average number of tuples per page or however you want
to think about it ...)
regards, tom lane