Message-Id: <200606230715.k5N7FHjO007409@auth-smtp.hol.gr>
From: "Forums @ Existanze" <forums@existanze.com>
To: <pgsql-sql@postgresql.org>
Subject: Re: Fwd: Start up question about triggers
Date: Fri, 23 Jun 2006 10:15:22 +0300
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Hello again aaron,

Im really interested in the part where you say "generic trigger" can you
give me some tips? As to how I will go about that? I had already read the
links that Richard gave, I new I could get the values like that. So right
now I will have to create a trigger for each of my tables to create the
necessary queries, or I could do it "generically" :-)

Best Regards,
Fotis

> -----Original Message-----
> From: pgsql-sql-owner@postgresql.org 
> [mailto:pgsql-sql-owner@postgresql.org] On Behalf Of Richard 
> Broersma Jr
> Sent: 23 June 2006 08:10
> To: Aaron Bono; pgsql-sql@postgresql.org
> Subject: Re: Fwd: [SQL] Start up question about triggers
> 
> > I did some research and can't even find a way to get meta 
> data in a trigger.
> > 
> > In a trigger, is there a way to inspect OLD and NEW to see what 
> > columns are there and see what has changed?  If so, you may not be 
> > able to grab the actual query but you could create a 
> generic trigger 
> > that reconstructs a possible update/insert/delete for any 
> table in your database.
> > 
> > Does anyone know of a good place to go get information about using 
> > meta data in a stored procedure or trigger?
> 
> yes.
> See the section "User Comments" at the very bottom of Chapter 
> 33 after "Writing Trigger Functions in C".  It is odd that a 
> PL_PGSQL example is given at the end a chapter for triggers 
> written in C.
> 
> http://www.postgresql.org/docs/8.1/interactive/trigger-example.html
> 
> Also see the entire chapter 36.10 "Trigger Procedures"
> http://www.postgresql.org/docs/8.1/interactive/plpgsql-trigger.html
> 
> Hope this is what you are looking for.
> 
> Regards,
> 
> Richard Broersma Jr.
> 
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