Date: Tue, 21 Aug 2018 19:55:57 +0200 (CEST)
From: Fabien COELHO <coelho@cri.ensmp.fr>
To: Pavel Stehule <pavel.stehule@gmail.com>
cc: Gilles Darold <gilles.darold@dalibo.com>,
    PostgreSQL Hackers <pgsql-hackers@lists.postgresql.org>
Subject: Re: [HACKERS] proposal: schema variables
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Hello Pavel,

AFAICR, I had an objection on such new objects when you first proposed 
something similar in October 2016.

Namely, if session variables are not transactional, they cannot be used to 
implement security related auditing features which were advertised as the 
motivating use case: an the audit check may fail on a commit because of a 
differed constraint, but the variable would keep its "okay" value unduly, 
which would create a latent security issue, the audit check having failed 
but the variable saying the opposite.

So my point was that they should be transactional by default, although I 
would be ok with an option for having a voluntary non transactional 
version.

Is this issue addressed somehow with this version?

-- 
Fabien.