Re: surrogate key or not? - Mailing list pgsql-sql

From Markus Bertheau
Subject Re: surrogate key or not?
Date
Msg-id 1090407515.3239.4.camel@dicaprio.akademie1.de
Whole thread Raw
In response to Re: surrogate key or not?  (sad <sad@bankir.ru>)
Responses Re: surrogate key or not?  (sad <sad@bankir.ru>)
List pgsql-sql
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>



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