Re: list of extended statistics on psql

From: Tatsuro Yamada <tatsuro(dot)yamada(dot)tf(at)nttcom(dot)co(dot)jp>
To: Tomas Vondra <tomas(dot)vondra(at)enterprisedb(dot)com>, Tomas Vondra <tomas(dot)vondra(at)2ndquadrant(dot)com>
Cc: Michael Paquier <michael(at)paquier(dot)xyz>, Pavel Stehule <pavel(dot)stehule(at)gmail(dot)com>, Alvaro Herrera <alvherre(at)2ndquadrant(dot)com>, Julien Rouhaud <rjuju123(at)gmail(dot)com>, PostgreSQL Hackers <pgsql-hackers(at)lists(dot)postgresql(dot)org>
Subject: Re: list of extended statistics on psql
Date: 2020-11-17 04:35:07
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Hi Tomas,

Thanks for your comments and also revising patches.

On 2020/11/16 3:22, Tomas Vondra wrote:
> It's better to always post the whole patch series, so that cfbot can
> test it properly. Sending just 0003 separately kind breaks that.

I now understand how "cfbot" works so that I'll take care of that
when I send patches. Thanks.

> Also, 0003 seems to only tweak the .sql file, not the expected output,
> and there actually seems to be two places that mistakenly use \dx (so
> listing extensions) instead of \dX. I've fixed both issues in the
> attached patches.

Oops, sorry about that.

> However, I think the 0002 tests are better/sufficient - I prefer to keep
> it compact, not interleaving with the tests testing various other stuff.
> So I don't intend to commit 0003, unless there's something that I don't
> see for some reason.

I Agreed. 0002 is easy to modify test cases and check results than 0003.
Therefore, I'll go with 0002.

> The one remaining thing I'm not sure about is naming of the columns with
> size of statistics - N_size, D_size and M_size does not seem very clear.
> Any clearer naming will however make the tables wider, though :-/

Yeah, I think so too, but I couldn't get an idea of a suitable name for
the columns when I created the patch.
I don't prefer a long name but I'll replace the name with it to be clearer.
For example, s/N_size/Ndistinct_size/.

Please find attached patcheds:
- 0001: Replace column names
- 0002: Recreate regression test based on 0001

Tatsuro Yamada

Attachment Content-Type Size
0002-v2-Add-regression-test-of-dX-command.patch text/plain 9.7 KB
0001-v9-Add-dX-command-on-psql.patch text/plain 7.9 KB

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