On Fri, Dec 23, 2022 at 10:21 AM Tom Lane <tgl@sss.pgh.pa.us> wrote:
Here's a new edition of this patch series.
I shoved some preliminary refactoring into the 0001 patch, notably splitting deconstruct_jointree into two passes. 0002-0009 cover the same ground as they did before, though with some differences in detail. 0010-0012 are new work mostly aimed at removing kluges we no longer need.
There are two big areas that I would still like to improve, but I think we've run out of time to address them in the v16 cycle:
* It'd be nice to apply the regular EquivalenceClass deduction mechanisms to outer-join equalities, instead of the reconsider_outer_join_clauses kluge. I've made several stabs at that without much success. I think that the "join domain" framework added in 0012 is likely to provide a workable foundation, but some more effort is needed.
* I really want to get rid of RestrictInfo.is_pushed_down and RINFO_IS_PUSHED_DOWN(), because those seem exceedingly awkward and squishy. I've not gotten far with finding a better replacement there, either.
Despite the work being unfinished, I feel that this has moved us a long way towards outer-join handling being less of a jury-rigged affair.
regards, tom lane
Hi,
For v8-0012-invent-join-domains.patch, in `distribute_qual_to_rels`, it seems that `pseudoconstant` and `root->hasPseudoConstantQuals` carry the same value.