Обсуждение: Trivial revise for the check of parameterized partial paths

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Trivial revise for the check of parameterized partial paths

От
Richard Guo
Дата:
While working on the invalid parameterized join path issue [1], I
noticed that we can simplify the codes for checking parameterized
partial paths in try_partial_hashjoin/mergejoin_path, with the help of
macro PATH_REQ_OUTER.

-       if (inner_path->param_info != NULL)
-       {
-               Relids          inner_paramrels = inner_path->param_info->ppi_req_outer;
-
-               if (!bms_is_empty(inner_paramrels))
-                       return;
-       }
+       if (!bms_is_empty(PATH_REQ_OUTER(inner_path)))
+               return;

Also there is a comment there that is not correct.

 * If the inner path is parameterized, the parameterization must be fully
 * satisfied by the proposed outer path.

This is true for nestloop but not for hashjoin/mergejoin.

Besides, I wonder if it'd be better that we verify that the outer input
path for a partial join path should not have any parameterization
dependency.

Attached is a patch for all these changes.

[1] https://www.postgresql.org/message-id/flat/CAJKUy5g2uZRrUDZJ8p-%3DgiwcSHVUn0c9nmdxPSY0jF0Ov8VoEA%40mail.gmail.com

Thanks
Richard
Вложения

Re: Trivial revise for the check of parameterized partial paths

От
vignesh C
Дата:
On Thu, 29 Jun 2023 at 08:53, Richard Guo <guofenglinux@gmail.com> wrote:
>
> While working on the invalid parameterized join path issue [1], I
> noticed that we can simplify the codes for checking parameterized
> partial paths in try_partial_hashjoin/mergejoin_path, with the help of
> macro PATH_REQ_OUTER.
>
> -       if (inner_path->param_info != NULL)
> -       {
> -               Relids          inner_paramrels = inner_path->param_info->ppi_req_outer;
> -
> -               if (!bms_is_empty(inner_paramrels))
> -                       return;
> -       }
> +       if (!bms_is_empty(PATH_REQ_OUTER(inner_path)))
> +               return;
>
> Also there is a comment there that is not correct.
>
>  * If the inner path is parameterized, the parameterization must be fully
>  * satisfied by the proposed outer path.
>
> This is true for nestloop but not for hashjoin/mergejoin.
>
> Besides, I wonder if it'd be better that we verify that the outer input
> path for a partial join path should not have any parameterization
> dependency.
>
> Attached is a patch for all these changes.

I'm seeing that there has been no activity in this thread for nearly 7
months, I'm planning to close this in the current commitfest unless
someone is planning to take it forward.

Regards,
Vignesh



Re: Trivial revise for the check of parameterized partial paths

От
Richard Guo
Дата:

On Sun, Jan 21, 2024 at 8:36 PM vignesh C <vignesh21@gmail.com> wrote:
I'm seeing that there has been no activity in this thread for nearly 7
months, I'm planning to close this in the current commitfest unless
someone is planning to take it forward.

This patch fixes the wrong comments in try_partial_hashjoin_path, and
also simplifies and enhances the checks for parameterized partial paths.
I think it's worth to be moved forward.

I've rebased the patch over current master, added a commit message
describing what it does, and updated the comment a little bit in the v2
patch.

Thanks
Richard
Вложения