Berkely Db. How to iterate over large number of keys "quickly"

[lazy]

Sorry, Just a small correction,

> a way I can tell Python to not load allkeys, but try to access it as
> the loop progresses(like in a linked list). I could find any accessor
> methonds on bsddb to this with my initial search.

I meant, "I couldn't find any accessor methonds on bsddb to do
this(i.e accesing like in a linked list) with my initial search"

> I am guessing BTree might be a good choice here, but since while the
> Dbs were written it was opened using hashopen, Im not able to use
> btopen when I want to iterate over the db.