Re: Performance issue in foreign-key-aware join estimation

On Sat, 9 Mar 2019 at 08:05, Tom Lane <tgl@sss.pgh.pa.us> wrote:
> Setting the CF entry to WOA for now.  I wonder though if we should
> just push it out to v13 immediately --- are you intending to do more
> with it in the near future?

Thanks a lot for going over this and providing feedback.  I put the
patch out there mostly to see if such a thing is something we might
want, and it's good to see no objections to the idea. I didn't want to
waste too much time if there was going to be some serious objections
to the idea.

This is something I'd like to look into for v13.  I think it'll be
much easier to do if we can get your List reimplementation patch in
first. That's going to allow list_nth on PlannerInfo->eq_classes to
work quickly and will remove the need for having to build an array to
store the classes, and as you mention, RelOptInfo could store a
Bitmapset to store which ECs have members for this rel.   I've
modified the CF entry to target v13.

-- 
 David Rowley                   http://www.2ndQuadrant.com/
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