Thread: Is there something similar like flashback query from Oracle planned for PostgreSQL

Hi,

just a curious question...

Is there something planned to get a behaviour like Oracle's flashback query based on the old values
before deleted by vacuum?

So a feature to recreate old versions of rows if still there?

Or are there any related extensions or tools doing this?

Thanks

Dirk




On Thu, 24 Jun 2021 at 00:24, Dirk Krautschick <Dirk.Krautschick@trivadis.com> wrote:
Hi,
Is there something planned to get a behaviour like Oracle's flashback query based on the old values
before deleted by vacuum?

So a feature to recreate old versions of rows if still there?

Or are there any related extensions or tools doing this?


postgresql has external  tools like barman that ship WALs to a different location for point in time recovery.
That way, you can restore the db to any point in the past since the time you were collecting WALs.

if this is not the same, then please ignore the above :)


--
Thanks,
Vijay
Mumbai, India
On Thu, Jun 24, 2021 at 6:54 AM Dirk Krautschick
<Dirk.Krautschick@trivadis.com> wrote:
> Is there something planned to get a behaviour like Oracle's flashback query based on the old values
> before deleted by vacuum?
>
> So a feature to recreate old versions of rows if still there?
>
> Or are there any related extensions or tools doing this?

There are some things like pg_dirtyread and probably more.  You might
be interested in some of the references in this thread:

https://www.postgresql.org/message-id/flat/CAKLmikOkK%2Bs0V%2B3Pi1vS2GUWQ0FAj8fEkVj9WTGSwZE9nRsCbQ%40mail.gmail.com

As for the SQL standard's approach to this, there are some active
-hackers threads on that with patches in development... look for
"temporal tables" and "system versioned".