Re: including backend ID in relpath of temp rels - updated patch

On Sun, Jul 25, 2010 at 2:37 AM, Jaime Casanova <jaime@2ndquadrant.com> wrote:
> but i have a few questions, maybe is right what you did i only want to
> understand it:
> - you added this in include/storage/smgr.h, so why is safe to assume
> that if the backend != InvalidBackendId it must be a temp relation?
>
> +#define SmgrIsTemp(smgr) \
> +   ((smgr)->smgr_rnode.backend != InvalidBackendId)

That's pretty much the whole point of the patch.  Instead of
identifying relations as simply "temporary" or "not temporary", we
identify as "a temporary relation owned by backend X" or as "not
temporary".

> - you added a question like this "if (rel->rd_backend == MyBackendId)"
> in a few places... why are you assuming that? that couldn't be a new
> created relation (in current session of course)? is that safe?

Again, rd_backend is not the creating backend ID unless the relation
is a temprel.

--
Robert Haas
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