Re: How to use as Functional Index to be used as Primary KEY

Am Samstag, 31. Juli 2004 17:13 schrieb Tom Lane:
> Janning Vygen <vygen@gmx.de> writes:
> > So here is my question: How can i define a functional index to be used
> > with a primary key (using postgreSQL 7.4.3)?
>
> You can't.  The SQL spec says that primary keys are columns or lists of
> columns.
>
> I don't see any particular difference between a primary key and a unique
> index, anyway, except that the primary key is the default target for
> foreign-key references.

Thanks to Tom and Peter for your answers. I will design my table without a
primary key and use my unique index instead of a primary key. As this unique
key is the same as a primary key i dont see the reason why postgresql
should't extend the specs and allow functional primary key indizes.

kind regards,
janning