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

Simon Riggs <simon@2ndQuadrant.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.

			regards, tom lane