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	Mon, 31 Aug 2020 10:58:11 -0400
From: Tom Lane <tgl@sss.pgh.pa.us>
To: Alvaro Herrera <alvherre@2ndquadrant.com>
cc: Tomas Vondra <tomas.vondra@2ndquadrant.com>,
        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
In-reply-to: <20200831142838.GA30609@alvherre.pgsql>
References: <20200831142838.GA30609@alvherre.pgsql>
Comments: In-reply-to Alvaro Herrera <alvherre@2ndquadrant.com>
	message dated "Mon, 31 Aug 2020 10:28:38 -0400"
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Date: Mon, 31 Aug 2020 10:58:11 -0400
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Alvaro Herrera <alvherre@2ndquadrant.com> writes:
> If we do put each type in its own row -- at least "logical" row, say
> string_agg(unnest(array_of_types), '\n') -- then we can put the size of =
each type
> in a separate column with string_agg(unnest(array_of_sizes), '\n') =


>  statname |   definition    |         type             |  size
> ----------+-----------------+--------------------------+-----------
>  someobj  | (a, b) FROM tab | n-distinct: built        | 2000 bytes
>                             | func-dependencies: built | 4000 bytes
>  another  | (a, c) FROM tab | n-distint: enabled       | <null>

I guess I'm wondering why the size is of such interest that we
need it at all here.

			regards, tom lane