From: Markus Bertheau <twanger@bluetwanger.de>
To: sad <sad@bankir.ru>
Cc: pgsql-sql@postgresql.org
Subject: Re: surrogate key or not?
Date: Wed, 21 Jul 2004 12:58:35 +0200
Message-ID: <1090407515.3239.4.camel@dicaprio.akademie1.de> (raw)
In-Reply-To: <200407211144.01001.sad@bankir.ru>
References: <1090325769.3241.27.camel@dicaprio.akademie1.de>
<004101c46ec2$631ca930$7201a8c0@mst1x5r347kymb>
<200407210001.00102.josh@agliodbs.com>
<200407211144.01001.sad@bankir.ru>
В Срд, 21.07.2004, в 09:44, sad пишет:
> 4) Replication: to identify an object of ANY type (record of any table
> regardless to datamodel), to store lists of deleted or modified objects
> (regardless to datamodel)
That sounds like a datamodel on data that belongs to another data model,
and 5) applies.
> 5) Making a primary key: if there is no real key at all.
When there's no key at all, there can't be a surrogate key, as I
understand it. In such cases a generated unique number comes in handy,
and it's a real primary key and no surrogate key.
Спасибо
--
Markus Bertheau <twanger@bluetwanger.de>
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Reply to all the recipients using the --to and --cc options:
reply via email
To: pgsql-sql@postgresql.org
Cc: twanger@bluetwanger.de, sad@bankir.ru
Subject: Re: surrogate key or not?
In-Reply-To: <1090407515.3239.4.camel@dicaprio.akademie1.de>
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
This inbox is served by DDX for PostgreSQL; see mirroring instructions
for how to clone and mirror all data and code used for this inbox