Re: mal advice in FAQ 4.1.

2007/10/9, Nikolay Samokhvalov <samokhvalov@gmail.com>:
> Hubert recently posted his thoughts on this topic:
> http://www.depesz.com/index.php/2007/09/16/my-thoughts-on-getting-random-row/
>
> I've encountered with this problem several times in web development and
> every time found out that the best (in terms of performance) solution is to
> use some pseudo random approach (such as ">= random() limit 1" or "limit 1
> offset random()*N" or even pre-caching rows on app side).
>

I know this article, but you cannot link from faq to private
(unstable) blog. it would article on techdoc.postgresql.org

Pavel

On 10/9/07, Pavel Stehule <pavel.stehule@gmail.com> wrote:
> > Hello
> >
> > I found lot of slow queries in some databases which I checked based on
> > advice 4.1. from FAQ,
> >
> > To SELECT a random row, use:
> >     SELECT col
> >     FROM tab
> >     ORDER BY random()
> >     LIMIT 1;
> >
> > It's robust and slow on bigger tables. Can we add some better solutions?
> >
>
>
> --
> Best regards,
> Nikolay