Re: [HACKERS] FOREIGN KEYs (Was: Benchmarking PGSQL against Microsoft SQL 7)

Hannu Krosing wrote:
> 
> Bruce Momjian wrote:
> >
> > That leaves foreign keys.  We really need to address this, because it
> > comes up so often.  Can we hash through the issues again, and see if
> > someone takes on the project.
> 
> If my memory servers me right:
> 
> Vadim _almost_ did implement FOREIGN KEY syntax just before 6.4 (or

I did nothing for syntax.

> 6.4.1 ?)
> using the trigger version in contrib.
> 
> But he stopped the work as he was unhappy with the way the contrib stuff
> worked  i.e. the keys can't break the rules even _during_ the statement.

I stopped just after starting -:)

> I wholly agree with this being broken, but it still would not hurt very
> because the same is unfortunately true for current primary keys/unique
> indexes, try for example

Yes, this would be nice, but I have no time/wish to do this - 
I would like to do "right" implementation someday. 
And for UNIQUE keys too.

> hannu=> update test set k=k+1;
> ERROR:  Cannot insert a duplicate key into a unique index
> 
> IMHO the right behaviour would be to allow this kind of updates, and I
> suspect that Oracle does allow it.

Sure.

Vadim