Re: multiple nodes in FDW create server statement

Vijaykumar Jain wrote:
> We are glad that we have this feature that allows us to load balance reads.
> that has helped us a lot.
> https://paquier.xyz/postgresql-2/postgres-10-multi-host-connstr/
>
> I would like to know if it is possible to request a similar enhancement to FDWs too?
> https://www.postgresql.org/docs/11/sql-createserver.html
>
> unless i am missing something obvious, we wanted to use this option when one
> of the read instances are down when there is a FDW query for reads.
> the second instance is only a fallback, not round robin. and we have
> 2 foreign servers, one for write and one for reads.

The documentation of postgres_fdw says:

A foreign server using the postgres_fdw foreign data wrapper can have the same
options that libpq accepts in connection strings, as described in Section 34.1.2,
except that these options are not allowed:

user and password (specify these in a user mapping, instead)

client_encoding (this is automatically set from the local server encoding)

fallback_application_name (always set to postgres_fdw)

So there is nothing that keeps you from using multiple host names or ports,
and you can also use "target_session_attrs".

Yours,
Laurenz Albe
--
Cybertec | https://www.cybertec-postgresql.com