Re: pgsql: Fix planner's use of Result Cache with unique joins

On Mon, 24 May 2021 at 02:14, Tom Lane <tgl@sss.pgh.pa.us> wrote:
> Coverity is not happy with this:

> This complaint is triggered because elsewhere in the same function,
> you're careful to check for inner_path->param_info being null before
> trying to dereference it:
>
>     if ((inner_path->param_info == NULL ||
>          inner_path->param_info->ppi_clauses == NIL) &&
>         innerrel->lateral_vars == NIL)
>         return NULL;
>
> Coverity reasons that it's probably a bug that you didn't do the same
> here; and I think it's right.

Yeah, I think that should be fixed. Thanks for reporting.

I propose the attached.  I think if the restrictlist is empty then we
needn't bother trying Result Cache.

David