Re: ORDER BY random() LIMIT 1 slowness

On Wed, Dec 18, 2002 at 02:09:42PM -0500, Jean-Luc Lachance wrote:
> OK Gabor,
>
> I'm the one who misunderstood.
>
> To me, it seem to be a bug (or at least a mis-feature) that one cannot
> call currval() before calling nextval().
>
> Does anyone know why it should be like this?

It doesn't make sense to call currval() if you haven't called nextval()
before.  The meaning of currval() is "the value that was last assigned
to you".  If you haven't called nextval(), there isn't a value assigned
to you.

If you want to know what was the last value the sequence gave to anyway,
SELECT last_value FROM sequence.  But be aware that this is
non-transaction safe, non-isolatable, non-anything.

--
Alvaro Herrera (<alvherre[a]dcc.uchile.cl>)
"Entristecido, Wutra
echa a Freyr a rodar
y a nosotros al mar" (cancion de Las Barreras)