Re: Random()

On 11/17/06, A. Kretschmer <andreas(dot)kretschmer(at)schollglas(dot)com> wrote:
> am Thu, dem 16.11.2006, um 16:31:14 -0200 mailte Ezequias Rodrigues da
> Rocha folgendes:
> > Hi list,
> >
> > I have a bigint collumn and I would like to generate a random number
> within the
> > numbers of my column.
>

> select <bigint_column> from <your_table> order by random() limit 1;

This query will tend to get slower as the table grows because of the sorting.

it possible to get a row from a random offset
how about

select <bigint_column> from <your_table> limit 1 offset 20000*random() ;

?

regds
mallah.

>
>
> Andreas
> --
> Andreas Kretschmer
> Kontakt: Heynitz: 035242/47215, D1: 0160/7141639 (mehr: -> Header)
> GnuPG-ID: 0x3FFF606C, privat 0x7F4584DA http://wwwkeys.de.pgp.net
>
> ---------------------------(end of broadcast)---------------------------
> TIP 1: if posting/reading through Usenet, please send an appropriate
> subscribe-nomail command to majordomo(at)postgresql(dot)org so that your
> message can get through to the mailing list cleanly
>