Re: newbie sql question: select every day another quote

On Sat, 12 May 2001, Janning Vygen wrote:

> Am Samstag, 12. Mai 2001 14:37 schrieb Len Morgan:
> > The "no result part" is harder.  You'll have to have some sort of client
> > program that can tell you if the above quote returned a row or not.  Once
> > you have that, if the above query did NOT return a row, you can use the
> > following two steps:
> >
> > UPDATE quotes SET lastdayshown = now():: WHERE oid = (SELECT oid FROM
> > quotes WHERE lastdayshown IS NULL LIMIT 1) ;
>
> i managed this now in php. works fine
> but the idea was to put this structure into the database, so the db user just
> have to send one select and once a day there is an automagical update.

It will probably work to make a plpgsql function doing something like:

1.  Figure out the primary key of today's quote
2.  Update the database if necessary
3.  Return the key of today's quote

then you can SELECT * from quotes WHERE key = todays_key();
--
Tod McQuillin