Re: Strange loop - Mailing list pgsql-sql

From Aasmund Midttun Godal
Subject Re: Strange loop
Date
Msg-id 20011030221216.23528.qmail@ns.krot.org
Whole thread Raw
In response to Strange loop  (Torbjörn Andersson <tobbe@embryo.se>)
List pgsql-sql
You are concatenating with a null value, which causes the result to be null.
See below, I have fixed it.

Regards,

Aasmund
On Tue, 30 Oct 2001 22:05:15 +0100, Torbjörn Andersson <tobbe@embryo.se> wrote:
> Hi,
> 
> I need some help with the function below. My intention is to hand the
> content of result_store and sort it out so that I can have a complete
> recordset. But for some reason result_store is returned empty. It works fine
> for one row but the concatenation of result_store and result does not seem
> to work.
> 
> Can some one pleas explain why?
> 
> 
> 
> CREATE FUNCTION f_snus()
> RETURNS varchar
> AS
> ' DECLARE
>         result varchar := '''';
>         result_store varchar := '''';
>         row record;
> BEGIN
>         FOR row IN
>                 SELECT snus_id, namn, betyg FROM snus ORDER BY betyg
>         LOOP
>                 SELECT INTO result row.snus_id || ''\t'' || row.namn ||
> ''\t'' || row.betyg  || ''\n'';
>                 result_store := result_store  || result;
>         END LOOP;
>         RETURN result_store;
> END;
> ' LANGUAGE 'PLPGSQL';
> 
> 
> 
> Regards
> 
> Torbjörn Andersson
> ---------------------------------------------------
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Aasmund Midttun Godal

aasmund@godal.com - http://www.godal.com/
+47 40 45 20 46


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