Re: A problem about ParamPathInfo for an AppendPath

On Tue, Dec 6, 2022 at 5:00 PM Richard Guo <guofenglinux(at)gmail(dot)com> wrote:

> As we can see, MemoizePath can be generated for partitioned AppendPath
> but not for union-all AppendPath.
>
> For the fix I think we can relax the check in create_append_path and
> always use get_baserel_parampathinfo if the parent is a baserel.
>

BTW, IIUC currently we don't generate any parameterized MergeAppend
paths, as explained in generate_orderedappend_paths. So the codes that
gather information from a MergeAppend path's param_info for run-time
partition pruning in create_merge_append_plan seem unnecessary.

Attached is a patch for this change and the changes described upthread.

Thanks
Richard