Hi Laurent,
> On 22. Oct, 2020, at 08:42, W.P. <laurentp(at)wp(dot)pl> wrote:
>
> Hi there,
>
> how to do "hot backup" (copying files) while database running?
>
> Not using pg_dump.
>
> Is there some equivalent of Oracle (I knew v8) "ALTER DATABASE BEGIN BACKUP", which froze writes to database files, pushing everything to redo files?
yes, there is. Please read the chapter: 25.3.3.1. Making A Non-Exclusive Low-Level Backup
https://www.postgresql.org/docs/current/continuous-archiving.html#BACKUP-LOWLEVEL-BASE-BACKUP
Cheers,
Paul