From: "Hayato Kuroda (Fujitsu)" <kuroda.hayato@fujitsu.com>
To: 'Michael Paquier' <michael@paquier.xyz>
CC: 'Peter Smith' <smithpb2250@gmail.com>, "Aya Iwata (Fujitsu)"
	<iwata.aya@fujitsu.com>, pgsql-hackers <pgsql-hackers@postgresql.org>
Subject: RE: [PROPOSAL] Termination of Background Workers for ALTER/DROP
 DATABASE
Thread-Topic: [PROPOSAL] Termination of Background Workers for ALTER/DROP
 DATABASE
Thread-Index: 
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Date: Thu, 9 Oct 2025 04:00:24 +0000
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Precedence: bulk

Dear Michael,

> > Sorry for posting many times. I noticed that CountOtherDBBackends() can=
 be
> called
> > while creating the database. Should we also mention and test the case?
>=20
> How would you test that?  A bgworker would not be able to connect to
> the database that's being created.
>

Sorry for missing words. Per my understanding, CountOtherDBBackends() in cr=
eatedb()
ensures that there are no active connections of the source database. If the=
re is
a connection to a database, we cannot create another database with TEMPALAT=
E clause:

```
postgres=3D# CREATE DATABASE new TEMPLATE postgres ;
ERROR:  source database "postgres" is being accessed by other users
DETAIL:  There is 1 other session using the database.
```

Based on that, I imagined that we could launch a bgworker and create anothe=
r database
by using template. Or is it already handled?

Best regards,
Hayato Kuroda
FUJITSU LIMITED