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

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.

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