Re: Rename max_parallel_degree?
Robert Haas <robertmhaas@gmail.com>
From: Robert Haas <robertmhaas@gmail.com>
To: Tom Lane <tgl@sss.pgh.pa.us>
Cc: Josh Berkus <josh@agliodbs.com>,
"David G. Johnston" <david.g.johnston@gmail.com>, Amit Kapila <amit.kapila16@gmail.com>, Peter Geoghegan <pg@heroku.com>,
Noah Misch <noah@leadboat.com>, David Rowley <david.rowley@2ndquadrant.com>,
Alvaro Herrera <alvherre@2ndquadrant.com>, Magnus Hagander <magnus@hagander.net>, Bruce Momjian <bruce@momjian.us>, PostgreSQL-development <pgsql-hackers@postgresql.org>
Date: 2016-06-08T14:47:43Z
Lists: pgsql-hackers
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
EnterpriseDB: http://www.enterprisedb.com
The Enterprise PostgreSQL Company