Re: Last ID Problem - Mailing list pgsql-novice

From Michael Fuhr
Subject Re: Last ID Problem
Date
Msg-id 20050201065027.GA53722@winnie.fuhr.org
Whole thread Raw
In response to Re: Last ID Problem  (Tom Lane <tgl@sss.pgh.pa.us>)
Responses Re: Last ID Problem  (Tom Lane <tgl@sss.pgh.pa.us>)
List pgsql-novice
On Tue, Feb 01, 2005 at 12:56:20AM -0500, Tom Lane wrote:
>
> His point stands though: if you are accessing Postgres through some kind
> of connection-pooling software, currval() cannot be trusted across
> transaction boundaries, since the pool code might give your connection
> to someone else.  In this situation the nextval-before-insert paradigm
> is the only way.

I don't disagree with that; if the thread mentioned connection
pooling then I must have overlooked it.

> (But in most of the applications I can think of, your uses of currval
> subsequent to an INSERT ought to be in the same transaction as the
> insert, so are perfectly safe.  If your connection pooler takes control
> away from you within a transaction block, you need a less broken
> pooler...)

That's the common situation I was talking about: doing an INSERT
and immediately calling currval(), presumably in the same transaction.
I should have been more clear about that and warned what could
happen in other situations.  Thanks.

--
Michael Fuhr
http://www.fuhr.org/~mfuhr/

pgsql-novice by date:

Previous
From: Tom Lane
Date:
Subject: Re: Last ID Problem
Next
From: Tom Lane
Date:
Subject: Re: Last ID Problem