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From: Tom Lane <tgl@sss.pgh.pa.us>
To: Craig James <cjames@emolecules.com>
cc: pgsql-admin@postgresql.org
Subject: Re: Mixing 8.4.x and 9.2.x clients and servers
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Comments: In-reply-to Craig James <cjames@emolecules.com>
	message dated "Tue, 09 Oct 2012 15:11:52 -0700"
Date: Tue, 09 Oct 2012 18:47:24 -0400
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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