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

On 2/6/19 10:59 PM, David Rowley wrote:
> On Thu, 7 Feb 2019 at 03:16, Alvaro Herrera <alvherre@2ndquadrant.com> wrote:
>> I wonder what should we be doing with this series -- concretely, should
>> the effort concentrate on one of the two patches, and leave the other
>> for pg13, to increase the chances of the first one being in pg12?  I
>> would favor that approach, since it's pretty late in the cycle by now
>> and it seems dubious that both will be ready.
> 
> I mostly have been reviewing the MCV patch with the thoughts that one
> is better than none in PG12.  I don't see any particular reason that
> we need both in the one release.
> 

I agree with that, although most of the complexity likely lies in
integrating the stats into the selectivity estimation - if we get that
right for the MCV patch, adding histogram seems comparably simpler.

But yeah, let's focus on the MCV part.

regards

-- 
Tomas Vondra                  http://www.2ndQuadrant.com
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