RE: BUG #16645: pg_upgrade does not mark template1 as a system database

I had created a ticket #5875 on pgAdmin 4 redmine.

However, after some grep-ing on pgAdmin4 source tree, I found that [System
Database?] shows pg_database.oid <= pg_database.datlastsysoid.

pg_database:
on initdb-ed 12.4:
oid datname datlastsysoid
1 template1 13317
13317 template0 13317
13318 postgres 13317

on pg_upgrade-d 13.0:
oid datname datlastsysoid
13441 template0 13441
16400 template1 13441
16401 postgres 13441

Are these differences by design?

Regards,
--
Y. Nakagawa

-----Original Message-----
From: Y. NAKAGAWA <nakagawa(at)goodf(dot)co(dot)jp>
Sent: Wednesday, September 30, 2020 1:11 PM
To: 'Tom Lane' <tgl(at)sss(dot)pgh(dot)pa(dot)us>
Cc: pgsql-bugs(at)lists(dot)postgresql(dot)org
Subject: RE: BUG #16645: pg_upgrade does not mark template1 as a system
database

Thank you for your suggestion.
According to pgAdmin4, [System database?] is [No] and [Template?] is [Yes].
I will post this to the pgadmin lists later.

Regards,

--
Nakagawa, Y.

-----Original Message-----
From: Tom Lane <tgl(at)sss(dot)pgh(dot)pa(dot)us>
Sent: Wednesday, September 30, 2020 11:46 AM
To: nakagawa(at)goodf(dot)co(dot)jp
Cc: pgsql-bugs(at)lists(dot)postgresql(dot)org
Subject: Re: BUG #16645: pg_upgrade does not mark template1 as a system
database

PG Bug reporting form <noreply(at)postgresql(dot)org> writes:
> 4. Open pgAdmin 4, connect to the PostgreSQL 13.0 server and expand
> the Databases node.
> Expected result:
> The node has [postgres].
> Actual result:
> The node has [postgres] and [template1].

There's no particular concept of a "system database" in Postgres, so I don't
know what pgadmin is doing to decide which databases to show or not show,
but evidently it's not too well thought out.

(The closest concept I can think of is whether a DB is marked datistemplate,
but a test confirms that pg_upgrade successfully preserves that property on
template0 and template1.)

I'd suggest you file this complaint on the pgadmin lists.

regards, tom lane