Re: Postgres upgrade 12 - issues with OIDs - Mailing list pgsql-general

From Venkata B Nagothi
Subject Re: Postgres upgrade 12 - issues with OIDs
Date
Msg-id CAEyp7J8Kc45E41b3v+gsyFFcYi2chraew9X4D17hKbbs++t1Uw@mail.gmail.com
Whole thread Raw
In response to Postgres upgrade 12 - issues with OIDs  (Venkata B Nagothi <nag1010@gmail.com>)
Responses Re: Postgres upgrade 12 - issues with OIDs
List pgsql-general
Missed including pgsql-general group. 

On Sat, 8 May 2021 at 11:06 am, Venkata B Nagothi <nag1010@gmail.com> wrote:


On Wed, 5 May 2021 at 9:22 am, Bruce Momjian <bruce@momjian.us> wrote:
On Wed, May  5, 2021 at 07:49:29AM +1000, Venkata B Nagothi wrote:
> Hi There,
>
> We are attempting to upgrade our Postgres databases from 9.5 to 12.5 using
> pg_upgrade link mode and are facing issues with OIDs.
>
> ALTER TABLE... SET WITHOUT OIDs on the larger tables is taking very long and is
> locking up the table as well. We do have tables of more than 1 TB of size. 
> Is there any way to make this complete faster ?  Any suggestions would be
> great. 

Uh, I see this on our code:

        pg_fatal("Your installation contains tables declared WITH OIDS, which is not\n"
                 "supported anymore.  Consider removing the oid column using\n"
                 "    ALTER TABLE ... SET WITHOUT OIDS;\n"
                 "A list of tables with the problem is in the file:\n"
                 "    %s\n\n", output_path);

Uh, I don't know of any way to speed that up, though it might be faster

That’s a big challenge for us as we want to achieve this with 0 down time to our live database and very minimal downtime to our DR.


if it was done while no one else was accessing the table.  I see this
comment in our PG 11 code:

    /*
     * If we dropped the OID column, must adjust pg_class.relhasoids and tell
     * Phase 3 to physically get rid of the column.  We formerly left the
     * column in place physically, but this caused subtle problems.  See
     * http://archives.postgresql.org/pgsql-hackers/2009-02/msg00363.php
     */

We are thinking to upgrade to PG 11 instead so that we can avoid doing ALTER TABLE.. SET WITHOUT OIDs. Does that makes sense ? Please advise if there are any gotchas !



--

Regards,

Venkata B N
Database Consultant
 
--

Regards,

Venkata B N
Database Consultant
 

pgsql-general by date:

Previous
From: Viral Shah
Date:
Subject: Re: Metric to calculate WAL size left to transfer to Standby
Next
From: Laurenz Albe
Date:
Subject: Re: Postgres upgrade 12 - issues with OIDs