Message-ID: <06286ee47fa4b06b6e7f08da21958d7e35525ed4.camel@j-davis.com>
Subject: Re: Statistics Import and Export
From: Jeff Davis <pgsql@j-davis.com>
To: Tom Lane <tgl@sss.pgh.pa.us>
Cc: Corey Huinker <corey.huinker@gmail.com>, Magnus Hagander
 <magnus@hagander.net>, Stephen Frost <sfrost@snowman.net>, Ashutosh Bapat
 <ashutosh.bapat.oss@gmail.com>, Matthias van de Meent
 <boekewurm+postgres@gmail.com>, Peter Smith <smithpb2250@gmail.com>,
 PostgreSQL Hackers <pgsql-hackers@lists.postgresql.org>, Tomas Vondra
 <tomas.vondra@enterprisedb.com>
Date: Tue, 02 Apr 2024 14:59:12 -0700
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On Tue, 2024-04-02 at 17:31 -0400, Tom Lane wrote:
> And that means that we don't need the sending
> side to know the element type anyway.

We need to get the original element type on the import side somehow,
right? Otherwise it will be hard to tell whether=C2=A0'{1, 2, 3, 4}' has
element type "int4" or "text", which affects the binary representation
of the anyarray value in pg_statistic.

Either we need to get it at export time (which seems the most reliable
in principle, but problematic for older versions) and pass it as an
argument to pg_set_attribute_stats(); or we need to derive it reliably
from the table schema on the destination side, right?

Regards,
	Jeff Davis