Message-ID: <419B56CC.8090703@archonet.com>
Date: Wed, 17 Nov 2004 13:49:00 +0000
From: Richard Huxton <dev@archonet.com>
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To: abief_ag_-postgresql@yahoo.com
Cc: pgsql-sql@postgresql.org
Subject: Re: session_id
References: <20041117131344.90253.qmail@web13922.mail.yahoo.com>
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Riccardo G. Facchini wrote:
> hi all,
> 
> is there a way to determine the session id on a database session?
> 
> I would need to have a unique number whenever a session is started, and
> have this available as a function or view result.

Add a new sequence to your database:
   CREATE SEQUENCE my_session_id;

Then, at the start of every session:
   SELECT nextval('my_session_id');

and whenever you need the value:
   SELECT currval('my_session_id');

Sequences are concurrency-safe, so you're OK with multiple clients. They 
return INT8 values, so you should be good for unique numbers for a while.

The only thing is, you need to remember to call nextval() every time you 
connect.

HTH
-- 
   Richard Huxton
   Archonet Ltd