Re: create summaries and update a second table?

On Wed, Jan 04, 2006 at 07:49:30PM +0100, Michelle Konzack wrote:
> Hello *,
>
> I have many tables (one per product) and the are two columns where I
> put my buyed and selled pieces.  Second I have a Main-Table with all
> products and a summary of the stock.
>
> What I want is, whenever I buy or sell something, the changements
> (buy/sell) in the product table must triger an update in the Main-
> Table.

See the end of
http://www.postgresql.org/docs/8.1/interactive/plpgsql-trigger.html.
Though one issue with that is there's a race condition in the
update/insert block. Ironically I just submitted a patch today to fix
that (see -patches archive), but in a nutshell you want to use the code
from example 34-1.
--
Jim C. Nasby, Sr. Engineering Consultant      jnasby@pervasive.com
Pervasive Software      http://pervasive.com    work: 512-231-6117
vcard: http://jim.nasby.net/pervasive.vcf       cell: 512-569-9461