| From: | Bruce Momjian <bruce(at)momjian(dot)us> |
|---|---|
| To: | Stephen Frost <sfrost(at)snowman(dot)net> |
| Cc: | Jerry Sievers <gsievers19(at)comcast(dot)net>, Scott Mead <scottm(at)openscg(dot)com>, Achilleas Mantzios <achill(at)matrix(dot)gatewaynet(dot)com>, PostgreSQL General <pgsql-general(at)postgresql(dot)org> |
| Subject: | Re: Uber migrated from Postgres to MySQL |
| Date: | 2016-07-29 19:09:38 |
| Message-ID: | 20160729190938.GI12810@momjian.us |
| Views: | Raw Message | Whole Thread | Download mbox | Resend email |
| Thread: | |
| Lists: | pgsql-general |
On Fri, Jul 29, 2016 at 02:50:32PM -0400, Stephen Frost wrote:
> > Er, using a not yet invented pg_downgrade:-)
>
> The short answer is 'no'. Consider a case like the GIN page changes- as
> soon as you execute DML on a column that has a GIN index on it, we're
> going to rewrite that page using a newer version of the page format and
> an older version of PG isn't going to understand it.
>
> Those kind of on-disk changes are, I suspect, why you have to set the
> "compatibility" option in the big $O product to be able to later do a
> downgrade.
Yes, you would need a mode that prevented new-format writes on the new
server.
--
Bruce Momjian <bruce(at)momjian(dot)us> http://momjian.us
EnterpriseDB http://enterprisedb.com
+ As you are, so once was I. As I am, so you will be. +
+ Ancient Roman grave inscription +
| From | Date | Subject | |
|---|---|---|---|
| Next Message | D'Arcy J.M. Cain | 2016-07-29 20:04:41 | Re: Allowing multiple versions of PG under NetBSD |
| Previous Message | Bruce Momjian | 2016-07-29 19:07:53 | Re: Uber migrated from Postgres to MySQL |