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From: Tom Lane <tgl@sss.pgh.pa.us>
To: Tomas Vondra <tomas.vondra@2ndquadrant.com>
cc: Andres Freund <andres@anarazel.de>,
        Dean Rasheed <dean.a.rasheed@gmail.com>,
        PostgreSQL Hackers <pgsql-hackers@postgresql.org>
Subject: Re: Multivariate MCV stats can leak data to unprivileged users
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Comments: In-reply-to Tomas Vondra <tomas.vondra@2ndquadrant.com>
	message dated "Sat, 18 May 2019 21:00:42 +0200"
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Tomas Vondra <tomas.vondra@2ndquadrant.com> writes:
> On Sat, May 18, 2019 at 11:49:06AM -0700, Andres Freund wrote:
>>> On Sat, 18 May 2019 at 16:13, Tom Lane <tgl@sss.pgh.pa.us> wrote:
>>>> It seems like what we need here is to have a separation between the
>>>> *definition* of a stats object (which is what pg_dump needs access
>>>> to) and the current actual *data* in it.

>> Otoh, having a suboptimal catalog representation that we'll likely have
>> to change in one of the next releases also isn't great. Seems likely
>> that we'll need post beta1 catversion bumps anyway?

> But that's not an issue intruduced by PG12, it works like that even for
> the extended statistics introduced in PG10.

Yeah, but no time like the present to fix it if it's wrong ...

			regards, tom lane