Re: [HACKERS] PATCH: multivariate histograms and MCV lists

On 04/07/2018 07:52 PM, Dean Rasheed wrote:
> On 7 April 2018 at 15:12, Bruce Momjian <bruce@momjian.us> wrote:
>> Uh, where are we on this patch?  It isn't going to make it into PG 11?
>> Feature development for this has been going on for years.
> 
> Unfortunately, I think there's no way that this will be ready for
> PG11. So far, I have only read parts of the patch, focusing mainly on
> the planner changes, and how it will make use of the new statistics. I
> think there are still issues to work out in that area, although I
> haven't read the latest version yet, I have some doubts about the new
> approach described.
> 
> Looking back at the history of this patch, it appears to have moved
> through all 4 PG11 commitfests with fairly minimal review, never
> becoming Ready for Committer. That's a real shame because I agree that
> it's an important feature, but IMO it's not yet in a committable
> state. I feel bad saying that, because the patch hasn't really had a
> fair chance to-date, despite Tomas' efforts and quick responses to all
> review comments.
> 

Well, yeah. The free fall through all PG11 commitfests is somewhat
demotivating :-/

I certainly agree the patch is not committable in the current state. I
don't think it's in terrible shape, but I'm sure there are still some
dubious parts. I certainly know about a few.

> At this stage though, all I can say is that I'll make every effort to
> keep reviewing it, and I hope Tomas will persist, so that it has a
> better chance in PG12.
> 

Thank you for the effort and for the reviews, of course.

regards

-- 
Tomas Vondra                  http://www.2ndQuadrant.com
PostgreSQL Development, 24x7 Support, Remote DBA, Training & Services