Horton

Re: [PATCH] Add extra statistics to explain for Nested Loop

David G. Johnston <david.g.johnston@gmail.com>

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From: "David G. Johnston" <david.g.johnston@gmail.com>
To: Anastasia Lubennikova <a.lubennikova@postgrespro.ru>
Cc: Julien Rouhaud <rjuju123@gmail.com>, Pavel Stehule <pavel.stehule@gmail.com>, e.sokolova@postgrespro.ru, PostgreSQL Hackers <pgsql-hackers@postgresql.org>
Date: 2020-10-17T15:11:34Z
Lists: pgsql-hackers 
On Fri, Oct 16, 2020 at 3:11 PM Anastasia Lubennikova <
a.lubennikova@postgrespro.ru> wrote:

> User visible change is:
>
>
> -               ->  Nested Loop (actual rows=N loops=N)
> +              ->  Nested Loop (actual min_rows=0 rows=0 max_rows=0
> loops=2)
>
I'd be inclined to append both new rows to the end.

(actual rows=N loops=N min_rows=N max_rows=N)

rows * loops is still an important calculation.

Why not just add total_rows while we are at it - last in the listing?

(actual rows=N loops=N min_rows=N max_rows=N total_rows=N)

David J.

Commits

  1. Fix wrong units in two ExplainPropertyFloat calls.