Re: findDependentObjects() mutual exclusion vs. MVCC catalog scans - Mailing list pgsql-hackers

Robert Haas <robertmhaas@gmail.com> writes:
> On Tue, Jul 16, 2013 at 9:50 AM, Noah Misch <noah@leadboat.com> wrote:
>> Let's fix this by having systable_recheck_tuple() acquire a fresh catalog MVCC
>> snapshot and recheck against that.  I believe it would also be fully safe to
>> use SnapshotNow here; however, I'm assuming we would otherwise manage to
>> remove SnapshotNow entirely.

I agree with Robert's comments, and in addition suggest that this code
needs a comment about why it's safe to use the snapshot without doing
RegisterSnapshot or equivalent.
        regards, tom lane