Re: Rename max_parallel_degree?

On Wed, Jun 8, 2016 at 10:41 AM, Tom Lane <tgl@sss.pgh.pa.us> wrote:
> Robert Haas <robertmhaas@gmail.com> writes:
>> On Wed, Jun 8, 2016 at 10:18 AM, Tom Lane <tgl@sss.pgh.pa.us> wrote:
>>> catversion is not relevant to GUC changes.  It's not really necessary,
>>> because you'd get a clean, easily diagnosed and repaired failure during
>>> postmaster startup anyway.  The point of bumping catversion is to prevent
>>> a postmaster starting when the incompatibility is subtler or harder to
>>> debug than that.
>
>> The reloption is also getting renamed here.
>
> Hmm.  I forget what the behavior is if we see an unrecognized reloption
> already stored in the catalogs, but it might be worth checking.  If
> that's something that's painful to get out of, maybe a catversion bump
> would be appropriate.

rhaas=# create table tgl (a int);
CREATE TABLE
rhaas=# alter table tgl set (parallel_degree = 3);
ALTER TABLE
rhaas=# select reloptions from pg_class where relname = 'tgl';    reloptions
---------------------{parallel_degree=3}
(1 row)

rhaas=# update pg_class set reloptions = '{beats_me=3}' where relname = 'tgl';
UPDATE 1
rhaas=# alter table tgl reset (beats_me);
ALTER TABLE
rhaas=# select reloptions from pg_class where relname = 'tgl';reloptions
------------

(1 row)

So it's not hard to get rid of.  pg_dump does dump the unrecognized
option, which will fail at restore time.

-- 
Robert Haas
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