Re: foreign join error "variable not found in subplan target list"

On Wed, Aug 31, 2022 at 6:52 PM Etsuro Fujita <etsuro.fujita@gmail.com> wrote:
> On Wed, Aug 31, 2022 at 6:27 PM Richard Guo <guofenglinux@gmail.com> wrote:
> > Hmm, yes, the EPQ path does not need to compete with others in add_path,
> > so its cost does not matter too much. And the comment just above
> > GetExistingLocalJoinPath says:
> >
> >  * Since the plan created using this path will presumably only be used to
> >  * execute EPQ checks, efficiency of the path is not a concern.
> >
> > But still I feel it's not a good practice to not update the cost and
> > width fields after calling add_new_columns_to_pathtarget(). How about we
> > add some comments here explaining why we do not need to adjust the
> > estimates for the EPQ path?
>
> I agree with you on that point.  I’ll update the patch as such in the
> next version.

Here is an updated patch for that.  Other changes:

* I modified the patch so that we adjust the tlist of the EPQ path if
necessary, using the idea discussed upthread.
* I tweaked other comments a little bit.