Message-ID: <b8cdd98b763215382197eaf4ab90e24ee0873768.camel@cybertec.at>
Subject: Re: How does Postgres support backwards compatibility
From: Laurenz Albe <laurenz.albe@cybertec.at>
To: Josh Innis <joshinnis@gmail.com>, pgsql-novice@lists.postgresql.org
Date: Wed, 09 Feb 2022 16:08:45 +0100
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On Tue, 2022-02-08 at 10:50 -0800, Josh Innis wrote:
> I work on an extension for Postgres. We originally developed the extension for Postgres 11.
> Now we are looking into supporting newer versions of Postgres. We would like our extension
> to be compatible with multiple versions of Postgres. Is there a document that explains how
> the Postgres community handles releases and supports older versions? Any information on how
> Postgres handles this will give us guidance on how to best approach this subject.

PostgreSQL won't break APIs wantonly, but particularly with server internal functions
this happens occasionally.

So it depends a lot on what your extension does.  If it is written in SQL, the odds
are good that it will just continue working.  If it is written in C and you use a lot
of server functions, chances are that you will have to decorate your code with conditional
directives like

#if PG_VERSION_NUM < 130000
...
#else
...
#endif

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