Subject: Re: Why the index is not used ?
To: ROS Didier <didier.ros@edf.fr>,
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Cc: "pavel.stehule@gmail.com" <pavel.stehule@gmail.com>,
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From: Tomas Vondra <tomas.vondra@2ndquadrant.com>
Message-ID: <f6ab9c6e-323f-8e2e-fd71-8f019045ff2b@2ndquadrant.com>
Date: Mon, 8 Oct 2018 22:00:15 +0200
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Hi,

On 10/08/2018 04:10 PM, ROS Didier wrote:
> Hi Tomas
>        
>         Thank you for your answer and recommendation which is very
> interesting. I'm going to study the PCI DSS document right now.
> 
>   * Here are my answer to your question :
> 
> />>/
> /What is your threat model?/
> /<</
> we want to prevent access to sensitive data for everyone except those
> who have the encryption key.
> in case of files theft, backups theft, dumps theft, we do not want
> anyone to access sensitive data.
>        

The thing is - encryption is not panacea. The interesting question is
whether this improves security compared to simply using FDE and regular
access rights (which are grantable at the column level).

Using those two pieces properly may very well be a better defense than
not well designed encryption scheme - and based on this discussion, it
does not seem very polished / resilient.


regards

-- 
Tomas Vondra                  http://www.2ndQuadrant.com
PostgreSQL Development, 24x7 Support, Remote DBA, Training & Services