Message-ID: <7f6e0ff9-05e9-4664-9c71-d9dd744362b9@gmail.com>
Date: Thu, 19 Mar 2026 08:44:15 +0100
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Subject: Re: Read-only connection mode for AI workflows.
From: Andrei Lepikhov <lepihov@gmail.com>
To: Jack Bonatakis <jack@bonatak.is>,
 pgsql-hackers <pgsql-hackers@postgresql.org>,
 Bruce Momjian <bruce.momjian@enterprisedb.com>,
 Andres Freund <andres@anarazel.de>
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On 16/3/26 22:01, Andrei Lepikhov wrote:
> On 16/3/26 20:28, Jack Bonatakis wrote:
>> On Mon, Mar 16, 2026, at 2:08 PM, Andrei Lepikhov wrote:
>>> I believe the pg_readonly [1] extension does what you're looking for, so
>>> you might want to give it a try.
>> Please correct me if I am mistaken, but it looks like pg_readonly 
>> operates at the database or cluster level. 

Take a look at the [1] project. It's a simpler version of [2] that 
always switches to read-only mode.
To use it, just have your connection pooler load the 'safesession' 
module. This will keep the session in read-only mode until it ends. 
There are no GUCs, and there is no way to change the mode, even for a 
superuser. Does this seem safe enough?

We could improve it by restricting manual calls to specific utility 
operations, such as VACUUM or REINDEX. However, we would need some 
specifications first.

[1] https://github.com/danolivo/safesession/
[2] https://github.com/pierreforstmann/pg_readonly

-- 
regards, Andrei Lepikhov,
pgEdge