Re: Modify Bootstrap user ID

I see below in an old version of the doc which mentions why it was cleared

Because MD5-encrypted passwords use the user name as cryptographic salt,
renaming a user clears their MD5 password

https://www.postgresql.org/docs/8.0/sql-alteruser.html#:~:text=The%20current%20session%20user%20cannot,for%20a%20specified%20configuration%20variable.

Thanks,
Nikhil

On Thu, 22 Feb 2024 at 19:01, Nikhil Shetty <nikhil(dot)dba04(at)gmail(dot)com> wrote:

> Hi Tom,
>
> We tried by renaming the user but it has removed the md5 password from
> pg_authid and we were not able to login
>
> We had to reset the password to make it work
>
> Thanks,
> Nikhil
>
> On Thu, 22 Feb 2024 at 00:09, Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us> wrote:
>
>> Nikhil Shetty <nikhil(dot)dba04(at)gmail(dot)com> writes:
>> > We want to upgrade a postgres v13 database to v16. but the bootstrap
>> user
>> > used to initialise the database for both are different
>> > Can we update the bootstrap user for v13 ? like assign oid as 10 in
>> > pg_authid?
>>
>> Do not try to change role OIDs --- you will certainly miss some
>> places where the OID appears. You can rename it though.
>>
>> You might have tried this:
>>
>> regression=# alter user postgres rename to pgsql;
>> ERROR: session user cannot be renamed
>>
>> but it's easy to get around that:
>>
>> regression=# create user joe superuser;
>> CREATE ROLE
>> regression=# \c - joe
>> You are now connected to database "regression" as user "joe".
>> regression=# alter user postgres rename to pgsql;
>> ALTER ROLE
>> regression=# \c - pgsql
>> You are now connected to database "regression" as user "pgsql".
>> regression=# drop user joe;
>> DROP ROLE
>>
>> regards, tom lane
>>
>