Re: WIP: BRIN multi-range indexes

On 2021-Mar-03, Tomas Vondra wrote:

> 1) The 0001 patch allows passing of all scan keys to BRIN opclasses,
> which is needed for the minmax-multi to work. But it also modifies the
> existing opclasses (minmax and inclusion) to do this - but for those
> opclasses it does not make much difference, I think. Initially this was
> done because the patch did this for all opclasses, but then we added the
> detection based on number of parameters. So I wonder if we should just
> remove this, to make the patch a bit smaller. It'll also test the other
> code path (for opclasses without the last parameter).

I think it makes sense to just do them all in one pass. I think trying
to keep the old way working just because it's how it was working
previously does not have much benefit. I don't think we care about the
*patch* being small as much as the resulting *code* being as simple as
possible (but no simpler).

> 2) This needs bsearch_arg, but we only have that defined/used in
> extended_statistics_internal.h - it seems silly to include that here, as
> this has nothing to do with extended stats, so I simply added another
> prototype (which gets linked correctly). But, I suppose a better way
> would be to define our "portable" variant pg_bsearch_arg, next to
> pg_qsort etc.

Yeah, I think it makes sense to move bsearch_arg to a place where it's
more generally accesible (src/port/bsearch_arg.c I suppose), and make
both places use that.

--
Álvaro Herrera Valdivia, Chile