Date: Sun, 30 Aug 2020 12:33:29 -0400
From: Alvaro Herrera <alvherre@2ndquadrant.com>
To: Tomas Vondra <tomas.vondra@2ndquadrant.com>
Cc: Tatsuro Yamada <tatsuro.yamada.tf@nttcom.co.jp>,
	Julien Rouhaud <rjuju123@gmail.com>,
	Pavel Stehule <pavel.stehule@gmail.com>,
	PostgreSQL Hackers <pgsql-hackers@lists.postgresql.org>
Subject: Re: list of extended statistics on psql
Message-ID: <20200830163329.GA21915@alvherre.pgsql>
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On 2020-Aug-30, Tomas Vondra wrote:

> On Sat, Aug 29, 2020 at 06:43:47PM -0400, Alvaro Herrera wrote:
> > On 2020-Aug-29, Tomas Vondra wrote:

> > > Also, it might be useful to show the size of the statistics built, just
> > > like we show for \d+ etc.
> > 
> > \dX+  I  suppose?
> 
> Right. I've only used \d+ as an example of an existing command showing
> sizes of the objects.

Yeah, I understood it that way too.

How can you measure the size of the stat objects in a query?  Are you
thinking in pg_column_size()?

I wonder how to report that.  Knowing that psql \-commands are not meant
for anything other than human consumption, maybe we can use a format()
string that says "built: %d bytes" when \dX+ is used (for each stat type),
and just "built" when \dX is used.  What do people think about this?

-- 
Álvaro Herrera                https://www.2ndQuadrant.com/
PostgreSQL Development, 24x7 Support, Remote DBA, Training & Services