Re: Out of date comment in cached_plan_cost

On 11 December 2017 at 21:39, Ashutosh Bapat
<ashutosh(dot)bapat(at)enterprisedb(dot)com> wrote:
> I don't see much difference in the old and new wording. The word
> "generally" confuses more than clarifying the cases when the planning
> cost curves do not change with the number of relations i.e.
> partitions.

I added that to remove the false claim that inheritance children don't
make the join problem more complex. This was only true before we had
partition-wise joins.

I've re-read my original patch and I don't really see the problem with
it. The comment is talking about inheritance child relations, which
you could either interpret to mean INHERITS (sometable), or some table
listed in pg_inherits. The statement that I added forces me into
thinking of the former rather than the latter, so I don't really see
any issue.

I'm going to leave it here. I don't want to spend too much effort
rewording a comment. My vote is for the original patch I sent. I only
changed it because Robert complained that technically an inheritance
child could actually be a partition.

--
David Rowley http://www.2ndQuadrant.com/
PostgreSQL Development, 24x7 Support, Training & Services