Re: ORDER BY random() LIMIT 1 slowness

Alvara,

But instead of returning an error, currval() should return last_value if
nextval() was not called (with all the caveat of couse). I think it
would be more usefull that way.

JLL

Alvaro Herrera wrote:
>
> 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)