From: Riccardo G. Facchini <abief_ag_-postgresql@yahoo.com>
To: Michael Fuhr <mike@fuhr.org>
To: pgsql-sql@postgresql.org
Subject: Re: session_id
Date: Thu, 18 Nov 2004 04:38:31 -0800 (PST)
Message-ID: <20041118123831.5789.qmail@web13925.mail.yahoo.com> (raw)
In-Reply-To: <20041117151939.GA4078@winnie.fuhr.org>
--- Michael Fuhr <__> wrote:
> On Wed, Nov 17, 2004 at 06:25:25AM -0800, Riccardo G. Facchini wrote:
> >
> > --- Richard Huxton <__> wrote:
> > >
> > > Add a new sequence to your database:
>
> [snip]
>
> > Good idea, but it won't work for what I need.
> > I'll be able to do get the nextval('my_session_id') as soon as the
> > session initiates, but my problem is that I need to make all the
> > subsecuent actions aware of that particular value. using
> > currval('my_session_id') is not good, as any other session is
> likely to
> > also change my_session_id to another value.
>
> Where did you get the idea that currval() would be affected by other
> sessions? Richard mentioned that sequences are concurrency-safe,
> as does the documentation.
>
> http://www.postgresql.org/docs/7.4/static/functions-sequence.html
>
> Can you give us an example of where this wouldn't work?
>
No, I can't provide it because your'e right. currval() is NOT affected
by other sessions.
Thanks anyway for the suggestion, using pg_backend_pid() solved the
uniqueness I needed. I'll keep the nextval/currval for another
opportunity.
thanks to all for the support!
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To: pgsql-sql@postgresql.org
Cc: abief_ag_-postgresql@yahoo.com, mike@fuhr.org
Subject: Re: session_id
In-Reply-To: <20041118123831.5789.qmail@web13925.mail.yahoo.com>
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