Re: PostgreSQL Replication with read-only access to standby DB

On Tue, 2008-03-25 at 14:11 -0600, Keaton Adams wrote:
> “All queries reading from the physical replica execute in real-time,
> and return current results. A Data Guard configuration consists of
> one production (or primary) database and up to nine standby
> databases. A standby database is initially created from a backup copy
> of the primary database. Once created, Data Guard automatically
> maintains the standby database as a synchronized copy of the primary
> database by transmitting primary database redo data to the standby
> system and then applying the redo data to the standby database.”
>
> Does anyone know of such a solution for PostgreSQL?
>

There has been work in this area, but unfortunately this feature has not
been completed yet. Many people would like this feature.

I have heard of a strategy used by some PostgreSQL users in which they
use something like ZFS (which allows fast filesystem snapshots/clones)
to quickly clone the data in a separate area, and then bring up the
database on the clone for reporting purposes.

This obviously does not work in real time, but it may be useful. It does
not require a lot of additional space to do this because of the ZFS
copy-on-write implementation.

Regards,
Jeff Davis