Re: Switch PG Versions

Edson,

Of course not. What you can do is install multiple versions of postgreSQL
in parallel (I've done it on Windows and Ubuntu Server). It's why they are
each put into their own version numbered directory. For example, a
Windows machine running versions 10, 12, and 13 would have a default file
structure like this;

C:\Program Files\PostgreSQL\10\... (various folders including data, where
your database data resides)
C:\Program Files\PostgreSQL\12\... (various folders including data, where
your database data resides)
C:\Program Files\PostgreSQL\13\... (various folders including data, where
your database data resides)

As you can see, as long as the data folders for each postgreSQL version are
kept in different locations and you are running postgreSQL on different
ports, you can run as many copies of postgreSQL in parallel as you have
resources (hard drive space, memory, CPU, etc.). Things only get tricky
when you want to run multiple instances of the *same* version of postgreSQL
on the same machine for some reason. In this case you would have to
deviate from the default folder structure. If you wanted to run three
copies of postgreSQL 13 on the same machine in parallel then something like
this would do;

C:\Program Files\PostgreSQL\13\... (various folders including data, where
your database data resides)
C:\Program Files\PostgreSQL\13a\... (various folders including data, where
your database data resides)
C:\Program Files\PostgreSQL\13b\... (various folders including data, where
your database data resides)

Of course, you would need to go back through your configuration files to
make sure they matched your alternative layout. You would also still need
to be running them on different ports.

I hope that helps,

rik.

On Thu, Mar 4, 2021 at 4:03 PM Edson Richter <edsonrichter(at)hotmail(dot)com>
wrote:

> Yes it’s possible to do as Richard noticed. But you cannot share at any
> chance the data folder!
>
> This will corrupt your data making irrecoverable.
>
> Even not having two versions online, you cannot shutdown version 10 and
> startup version 12 (or any combination of major versions) on same data
> folder – this will lead to data loss.
>
>
>
> Regards,
>
>
>
> Edson
>
>
>
> Enviado do Email <https://go.microsoft.com/fwlink/?LinkId=550986> para
> Windows 10
>
>
> ------------------------------
> *De:* Richard Brockie <richard(dot)brockie(at)gmail(dot)com>
> *Enviado:* Thursday, March 4, 2021 5:49:05 PM
> *Para:* pgadmin-support lists.postgresql.org <
> pgadmin-support(at)lists(dot)postgresql(dot)org>
> *Assunto:* Re: Switch PG Versions
>
> Hi Jack,
>
> I was in a similar situation with an old application using pg v9. I
> installed different versions of postgres with homebrew on Catalina. I
> currently have versions 9, 11 & 12 installed and can have them all running
> in parallel listening on different ports. I connect to them all from a
> single instance of pgAdmin4 over their respective ports. Testing the
> application with the new pg version is also just a port change in the
> configuration. It works very well.
>
> Best wishes,
> R.
>
>
> On Thu, Mar 4, 2021 at 11:52 AM Jack Royal-Gordon <jackrg(at)pobox(dot)com>
> wrote:
>
> I’m using the EDB PG installation on Mac OS 11.1 (Big Sur), which seems to
> offer multiple versions. I’m currently running PG10, but I’m looking to
> upgrade to PG13 and would like to test with it first. Can I (and if so then
> how do i) switch back and forth between PG versions?
>
>
>
> --
> R.
>
> Richard Brockie
>
> Real-time bicycle race management - www.ontheday.net
>