Re: copy databases from two differend backups to one cluster

On 11/18/22 04:33, Joseph Kennedy wrote:
> I would like to copy databases from two different pg_basebackup backups
> to one lab environment database cluster on another server. Is it possible ?
>
> It's a good idea to do it in that way.
>
> Databases has your oid in pg_basebackup we can find it id in base
> directory for example:

> Is it a good or  very bad idea ?

Bad idea.

For why see:

https://www.postgresql.org/docs/current/storage-file-layout.html

and

https://www.postgresql.org/docs/current/storage-page-layout.html

There is more to a cluster then what is found in a given databases
directory. You can't, at the file(binary) level, just rip a database out
of one cluster and graft it into another.

If you want to do this then the options are:

1) As Ron suggested dump/restore.

2) Setting up logical replication.

>
>
>

--
Adrian Klaver
adrian(dot)klaver(at)aklaver(dot)com