Re: v12.0: ERROR: could not find pathkey item to sort

Justin Pryzby <pryzby@telsasoft.com> writes:
> I've reduced the failing query as much as possible to this:
> -- This is necessary to fail:
> SET enable_nestloop=off;

> SELECT * FROM
>         (SELECT start_time, t1.site_id
>         FROM pgw_kpi_view t1
>         -- Apparently the where clause is necessary to fail...
>         WHERE (start_time>='2019-10-10' AND start_time<'2019-10-11')
>         -- The group by MAY be necessary to fail...
>         GROUP BY 1,2
>         ) AS data
> JOIN sites ON ( sites.site_location='' OR sites.site_office=data.site_id)

> The view is actually a join of two relkind=p partitioned tables (which I
> will acknowledge probably performs poorly).

Could you provide a self-contained test case please?

            regards, tom lane