Re: [GNUe-dev] Unique IDs in GNUe Appserver

[Leandro Guimarães Faria Corcete Dutra]

On Sun, 2003-06-01 at 18:07, Reinhard Mueller wrote:
> Am Son, 2003-06-01 um 17.49 schrieb Leandro Guimarães Faria Corcete
> Dutra:

> Using the natural key as primary key has several drawbacks:
> * Often, you result in compound primary keys, which are not easy to
> handle
> * Changing the value of such a key is quite expensive (for example
> changing the item number becaus of a reorganization)
> * Changing the format of such a key (for example expanding the item
> number from 15 to 20 characters) can be a big problem

        With the requisite facilities in the DBMS none of this should be a
problem.  And surrogate keys have a way of requiring that the natural
key be declared as unique, creating overhead.

        Now if we must support substandard DBMSs-lookalikes...


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