Re: BUG #17212: pg_amcheck fails on checking temporary relations

On Mon, Oct 11, 2021 at 1:20 PM Mark Dilger
<mark(dot)dilger(at)enterprisedb(dot)com> wrote:
> Ok, I went with this suggestion, and also your earlier suggestion to have a <warning> in the pg_amcheck docs about using --parent-check and/or --rootdescend against servers in recovery.

My concern with --parent-check (and with --rootdescend) had little to
do with Hot Standby. I suggested using a warning because these options
alone can pretty much cause bedlam on a production database. At least
if they're used carelessly. Again, bt_index_parent_check()'s relation
level locks will block all DML, as well as VACUUM. That isn't the case
with any of the other pg_amcheck options, including those that call
bt_index_check(), and including the heapam verification functionality.

It's also true that --parent-check won't work in Hot Standby mode, of
course. So it couldn't hurt to mention that in passing, at the same
point. But that's a secondary point, at best. We don't need to use a
warning box because of that.

Overall, your approach looks good to me. Will Robert take care of
committing this, or should I?

--
Peter Geoghegan