Horton

Re: preserving db/ts/relfilenode OIDs across pg_upgrade (was Re: storing an explicit nonce)

Shruthi Gowda <gowdashru@gmail.com>

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From: Shruthi Gowda <gowdashru@gmail.com>
To: Robert Haas <robertmhaas@gmail.com>
Cc: Tom Lane <tgl@sss.pgh.pa.us>, Stephen Frost <sfrost@snowman.net>, Bruce Momjian <bruce@momjian.us>, Andres Freund <andres@anarazel.de>, Alvaro Herrera <alvherre@alvh.no-ip.org>, Masahiko Sawada <sawada.mshk@gmail.com>, Tom Kincaid <tomjohnkincaid@gmail.com>, Amit Kapila <amit.kapila16@gmail.com>, Thomas Munro <thomas.munro@gmail.com>, PostgreSQL Development <pgsql-hackers@postgresql.org>, Masahiko Sawada <masahiko.sawada@2ndquadrant.com>
Date: 2021-08-17T18:07:24Z
Lists: pgsql-hackers

Commits

Same data as JSON: GET /api/v1/messages/:b64id/commits the thread's linked commits as JSON, with link sources. API reference →

  1. Rethink method for assigning OIDs to the template0 and postgres DBs.

  2. pg_upgrade: Preserve database OIDs.

  3. pg_upgrade: Preserve relfilenodes and tablespace OIDs.

  4. Fix for new Boolean node

  5. Improve error handling of HMAC computations

  6. Add macro RelationIsPermanent() to report relation permanence

  7. Enhance nbtree index tuple deletion.

On Tue, Aug 17, 2021 at 11:07 PM Robert Haas <robertmhaas@gmail.com> wrote:
>
> On Tue, Aug 17, 2021 at 12:42 PM Tom Lane <tgl@sss.pgh.pa.us> wrote:
> > Actually though ... I've not read the patch, but what does it do about
> > the fact that the postgres and template0 DBs do not have stable OIDs?
> > I cannot imagine any way to force those to match across PG versions
> > that would not be an unsustainable crock.
>
> Well, it's interesting that you mention that, because there's a
> comment in the patch that probably has to do with this:
>
> +    /*
> +     * Make sure that pg_upgrade does not change database OID. Don't care
> +     * about "postgres" database, backend will assign it fixed OID anyway.
> +     * ("template1" has fixed OID too but the value 1 should not collide with
> +     * any other OID so backend pays no attention to it.)
> +     */
>
In the original patch the author intended to avoid dumping the
postgres DB OID like below:
+ if (dopt->binary_upgrade && dbCatId.oid != PostgresDbOid)

Since postgres OID is not hardcoded/fixed I removed the check.
My bad I missed updating the comment section. Sorry for the confusion.

Regards,
Shruthi KC
EnterpriseDB: http://www.enterprisedb.com