Re: Multivariate MCV stats can leak data to unprivileged users

Hi,

On 2019-05-16 14:28:03 +0100, Dean Rasheed wrote:
> 5). Some columns from pg_statistic_ext have to be made visible for
> psql \d to work. Basically, it needs to be able to query for the
> existence of extended statistics, but it doesn't need to see the
> actual statistical data. Of course, we could change psql to use the
> view, but this way gives us better backwards compatibility with older
> clients.
>
> This is still going to break compatibility of any user code looking at
> stxndistinct or stxdependencies from pg_statistic_ext, but at least it
> doesn't break old versions of psql.

Hm, it's not normally a goal to keep old psql working against new
postgres versions. And there's plenty other issues preventing a v11 psql
to work against 12. I'd not let this guide any design decisions.

Greetings,

Andres Freund