Re: Foreign join pushdown vs EvalPlanQual

> > On Sun, Nov 8, 2015 at 7:26 PM, Kouhei Kaigai <kaigai(at)ak(dot)jp(dot)nec(dot)com> wrote:
> > > The attached patch is an adjusted version of the previous one.
> > > Even though it co-exists a new callback and fdw_recheck_quals,
> > > the callback is kicked first as follows.
> >
> > This seems excessive to me: why would we need an arbitrary-length list
> > of plans for an FDW? I think we should just allow an outer child and
> > an inner child, which is probably one more than we'll ever need in
> > practice.
> >
> It just intends to keep code symmetry with custom-scan case, so not
> a significant reason.
> And, I expected ForeignScan will also need multiple sub-plans soon
> to support more intelligent push-down like:
> http://www.postgresql.org/message-id/9A28C8860F777E439AA12E8AEA7694F8010F47D
> A(at)BPXM15GP(dot)gisp(dot)nec(dot)co(dot)jp
>
> It is a separate discussion, of course, so I don't have strong preference
> here.
>
> > This looks like an independent bug fix:
> >
> > + fscan->fdw_recheck_quals = (List *)
> > + fix_upper_expr(root,
> > + (Node *)
> > fscan->fdw_recheck_quals,
> > + itlist,
> > + INDEX_VAR,
> > + rtoffset);
> > pfree(itlist);
> >
> > If so, it should be committed separately and back-patched to 9.5.
> >
> OK, I'll split the patch into two.
>
The attached patch is the portion cut from the previous EPQ recheck
patch.

Regarding of the fdw_plans or fdw_plan, I'll follow your suggestion.

Thanks,
--
NEC Business Creation Division / PG-Strom Project
KaiGai Kohei <kaigai(at)ak(dot)jp(dot)nec(dot)com>