Thread: Mixing 8.4.x and 9.2.x clients and servers

Is it OK to mix 9.2.x and 8.4.x clients and servers?  Can they talk to each other?  In other words, if I install 9.2 on a new server alongside older servers running 8.4.x, can clients on the 8.4 systems talk to 9.2 servers, and can the 9.2 clients talk to 8.4 servers?

Thanks,
Craig

Craig James <cjames@emolecules.com> writes:
> Is it OK to mix 9.2.x and 8.4.x clients and servers?  Can they talk to each
> other?  In other words, if I install 9.2 on a new server alongside older
> servers running 8.4.x, can clients on the 8.4 systems talk to 9.2 servers,
> and can the 9.2 clients talk to 8.4 servers?

In general, sure.  There might be some specific incompatibilities (for
instance, 9.2 clients expecting server features that weren't there in
8.4) but the protocol is the same.

            regards, tom lane

Tom Lane wrote:
> Craig James <cjames@emolecules.com> writes:
> > Is it OK to mix 9.2.x and 8.4.x clients and servers?  Can they talk
to each
> > other?  In other words, if I install 9.2 on a new server alongside
older
> > servers running 8.4.x, can clients on the 8.4 systems talk to 9.2
servers,
> > and can the 9.2 clients talk to 8.4 servers?

> In general, sure.  There might be some specific incompatibilities (for
> instance, 9.2 clients expecting server features that weren't there in
> 8.4) but the protocol is the same.

One incompatibility that might bite you when an 8.4 client talks to a
9.2 server is the bytea encoding - unless you set "bytea_output" to
"escape" on the server, the client will choke on bytea values.

There are probably other small issues.

Yours,
Laurenz Albe