Re: libpq backwards compatbility

On Wed, Nov 2, 2016 at 11:58 PM, Andy Halsall <andyh@live.co.uk> wrote:
> Can we assume that the 9.6 libpq library is backwards compatible with
> applications compiled against 9.3 headers? I wouldn't expect to have to
> re-compile our application against 9.6 libpq headers and redeploy because
> we're not taking advantage of any new features and nothing seems to have
> been deprecated.
>
> The release notes talk about additions to libpq in section E.2.3.9 "Client
> Interfaces". I'd expect any un-changed features to be backwards compatible.
> Limited testing suggests this is so but I can't find a clear statement.
>
> Could somebody please advise?

libpq has a long history of keeping a backward-compatible interface
across the ages, and that pays in the long term. Your application
compiled with 9.3 headers would link to libpq.so.5, so that would be
binary-compatible with 9.6. For consistency's sake, you may want to
recompile it anyway.
--
Michael