On Fri, 9 Oct 2020 at 12:59, Tom Lane <t...@sss.pgh.pa.us> wrote: > If we did want to do something here, I'd consider something like > > if (isnan(outer_skip_rows)) > outer_skip_rows = 0; > if (isnan(inner_skip_rows)) > inner_skip_rows = 0;
Are you worried about the costs above the join that triggers that coming out as NaN with that fix? It appears that's the case. Cost comparisons of paths with that are not going to do anything along the lines of sane. I guess whether or not that matters depends on if we expect any real queries to hit this, or if we just want to stop the Assert failure. ... 500 joins. I'm willing to listen to the explanation use case, but in absence of that explanation, I'd be leaning towards "you're doing it wrong". If that turns out to be true, then perhaps your proposed fix is okay. David
