Robert Haas <robertmh...@gmail.com> writes: > On Sun, Jul 3, 2016 at 1:14 PM, Tom Lane <t...@sss.pgh.pa.us> wrote: >> I think a cleaner way is to have set_append_rel_size() invoke >> set_rel_consider_parallel() on the child rels and then propagate their >> parallel-unsafety up to the parent. That seems fairly analogous to >> the way we already deal with their sizes: in particular, set_rel_size >> is invoked on an appendrel child from there, not from an extra pass in >> set_base_rel_sizes. Then set_append_rel_pathlist can propagate unsafety >> down again, as you've done here.
> I was reluctant to do it that way because of the relatively stupid way > that we have to go about finding the inheritance children to visit, > but maybe I shouldn't let that dominate my thinking. We could always > replace that with some more efficient data structure at some point > down the road. That might be a reasonable objection if we needed to add a third such loop, but I'm talking about putting the set_rel_consider_parallel call in the loop that already exists. So there shouldn't be any added overhead. (It's definitely true that we could improve on the append_rel_list-based search mechanism; but so far I have never seen any indication that that was a bottleneck, so it's pretty far down my to-do list.) >> You mentioned that you'll be on vacation for much of July. If you like, >> I will take this open item off your hands, since I'll be around and can >> deal with any bugs that pop up in it. > That would be much appreciated. OK, will do. regards, tom lane -- Sent via pgsql-hackers mailing list (firstname.lastname@example.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers