Re: Partitioning...

On Mon, Jun 12, 2006 at 06:58:06PM -0400, Tom Lane wrote:
> "Milen Kulev" <makulev(at)gmx(dot)net> writes:
> > What is wrong with random() ?
>
> Not guaranteed to be stable across the multiple evaluations that the
> rule will perform ... remember a rule is a macro and has the usual
> multiple-evaluation gotchas in the face of volatile arguments.

I believe a safe alternative would be...

INSERT INTO ... SELECT * FROM
(SELECT random()*20 FROM ...)
;

You might need to add an ORDER BY to the subquery to ensure PostgreSQL
doesn't pull it into the main query.
--
Jim C. Nasby, Sr. Engineering Consultant jnasby(at)pervasive(dot)com
Pervasive Software http://pervasive.com work: 512-231-6117
vcard: http://jim.nasby.net/pervasive.vcf cell: 512-569-9461