Hannu Krosing <hannu(at)skype(dot)net> writes:
> A more radical variation of the "restricted-use archive table" approach
> is storing all tuple visibility info in a separate file.
> At first it seems to just add overhead, but for lots (most ? ) usecases
> the separately stored visibility should be highly compressible, so for
> example for bulk-loaded tables you could end up with one bit per page
> saying that all tuples on this page are visible.
The more you compress, the slower and more complicated it will be to
access the information. I'd put my money on this being a net loss in
the majority of scenarios.
regards, tom lane