I don't know how efficient it would be, but you could always do:
select * from mytable order by random() limit 1;
-philip
On Thu, 20 Dec 2001, Salvatore Sferrazza wrote:
> I've implemented something like this before, the way we solved it was by
> having a list of "candidate" images in a table indexed by some entity. We
> then used the front end tool (in our case, Java) to select the candidates,
> cache them and then pull randomly from the cache upon rendering the
> page. Asking SQL to do this may not be the best idea, since you don't
> want one more round-trip per page.
>
> HTH,
>
> Sal
>
> On Fri, 21 Dec 2001, Kris-Jon Fenton wrote:
>
> > Yes, I do have a question, how do I do this?
> >
> > -----Original Message-----
> > From: pgsql-novice-owner@postgresql.org
> > [mailto:pgsql-novice-owner@postgresql.org]On Behalf Of Josh Berkus
> > Sent: Friday, 21 December 2001 2:41 AM
> > To: Kris-Jon Fenton; pgsql-novice@postgresql.org
> > Subject: Re: FW: Random Selection from TABLE
> >
> >
> > Kris,
> >
> > > I want to be able to select entries randomly so I can change the
> > > images on a
> > > website using PHP.
> > >
> > > Basically I need to have a randomly rotating image that will change
> > > whenever
> > > the page is refreshed.
> > >
> > > I want to store the image names in a table and have them selected
> > > from
> > > there.
> >
> > Sounds like fun! Do you have a question for the list?
> >
> > -Josh
> >
> > ______AGLIO DATABASE SOLUTIONS___________________________
> > Josh Berkus
> > Complete information technology josh@agliodbs.com
> > and data management solutions (415) 565-7293
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