Re: [HACKERS] More stats about skipped vacuums

On Sat, Nov 25, 2017 at 12:09 PM, Tom Lane <tgl@sss.pgh.pa.us> wrote:
> Robert Haas <robertmhaas@gmail.com> writes:
>> Of course, the other obvious question is whether we really need a
>> consistent snapshot, because that's bound to be pretty expensive even
>> if you eliminate the I/O cost.  Taking a consistent snapshot across
>> all 100,000 tables in the database even if we're only ever going to
>> access 5 of those tables doesn't seem like a good or scalable design.
>
> Mumble.  It's a property I'm pretty hesitant to give up, especially
> since the stats views have worked like that since day one.  It's
> inevitable that weakening that guarantee would break peoples' queries,
> probably subtly.

You mean, queries against the stats views, or queries in general?  If
the latter, by what mechanism would the breakage happen?

-- 
Robert Haas
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