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From: Tom Lane <tgl@sss.pgh.pa.us>
To: Mark Dilger <mark.dilger@enterprisedb.com>
cc: Robert Haas <robertmhaas@gmail.com>, Noah Misch <noah@leadboat.com>,
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Subject: Re: pg_amcheck contrib application
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Comments: In-reply-to Mark Dilger <mark.dilger@enterprisedb.com>
	message dated "Tue, 16 Mar 2021 11:24:33 -0700"
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Date: Tue, 16 Mar 2021 14:52:22 -0400
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Mark Dilger <mark.dilger@enterprisedb.com> writes:
> CopyStatistics seems to just copy Form_pg_statistic without regard for
> who owns the toast.  Is this safe?

No less so than a ton of other places that insert values that might've
come from on-disk storage.  heap_toast_insert_or_update() is responsible
for dealing with the problem.  These days it looks like it's actually
toast_tuple_init() that takes care of dereferencing previously-toasted
values during an INSERT.

			regards, tom lane