Re: "xmin" system column - Mailing list pgsql-general

From Christian Kratzer
Subject Re: "xmin" system column
Date
Msg-id 20060127111619.U76989@vesihiisi.cksoft.de
Whole thread Raw
In response to Re: "xmin" system column  ("Eric B. Ridge" <ebr@tcdi.com>)
Responses Re: "xmin" system column  ("Jim C. Nasby" <jnasby@pervasive.com>)
List pgsql-general
Hi,

On Thu, 26 Jan 2006, Eric B. Ridge wrote:
<snip/>
> <long pause>
>
> hahaha, *blush*.  I could just use "now()", right?  pg8.1 docs say that
> now()/CURRENT_TIMESTAMP "return the start time of the current transaction;
> their values do not change during the transaction".  I could use a composite
> of (now(), GetTopTransctionId()) to assume batch uniqueness.

Or use a touple of (now(), pg_backend_pid()) for this kind of stuff.
pg_backend_pid() should sufficiently disambiguate now() to make obove
touple unique.

Greetings
Christian

--
Christian Kratzer                       ck@cksoft.de
CK Software GmbH                        http://www.cksoft.de/
Phone: +49 7452 889 135                 Fax: +49 7452 889 136

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