Re: [COMMITTERS] pgsql: Collect and use multi-column dependency stats

On 6 April 2017 at 17:41, David Rowley <david(dot)rowley(at)2ndquadrant(dot)com> wrote:
> On 7 April 2017 at 00:47, Simon Riggs <simon(at)2ndquadrant(dot)com> wrote:
>> On 5 April 2017 at 18:48, Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> wrote:
>>> Simon Riggs <simon(at)2ndQuadrant(dot)com> writes:
>>>> Collect and use multi-column dependency stats
>>>
>>> The buildfarm is unhappy about the fact that this changed the API
>>> for clauselist_selectivity(). I am not convinced that that change
>>> was a good idea, so before telling FDW authors that they need to
>>> change their code, I'd like to hear a defense of the API change.
>>> Why not just use the existing varRelid parameter for that? Why
>>> is there an assumption that only one rel's extended stats will
>>> ever be of interest? This function does get used for join clauses.
>>
>> Point noted. Reading thread and hope to fix today.
>
> I've attached a rebased patch which fixes up the conflict with the
> BRIN cost estimate patch which went in a short while ago.

Looks enough to me, for now at least. Minor comment added.

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