Function xxxx() does no exist

I've already sent this request for help to the novice mail list but I <br />never get any answer. So I wonder if it
wasthe good list for that kind <br />of question and I'm publishing it here. <br />(thousand of apologies if I'm wrong
!)<p>I'm a beginner with postgres and I'm trying to understand how I can <br />workaround the FOREIGN KEY mechanism
withinPostgres. <p>I've read that it's not supported yet (before rel 7) and I can use a trigger but I have some trouble
witha Function. <p>So I created: <br />CREATE TABLE "tbl_article" ( <br />   "i_article" serial PRIMARY KEY, <br />  
"repere"text, <br />   "refmedia" int4 NOT NULL, <br />   "theme" int4 NOT NULL, <br />   "mot_cle1" int4 NOT NULL, <br
/>  "mot_cle2" int4, <br />   "mot_cle3" int4); <p>and: <br /> CREATE TABLE "tbl_theme" ( <br />    "i_theme" serial
PRIMARYKEY, <br />    "theme" text NOT NULL UNIQUE); <p>then: <br />  CREATE FUNCTION chk_itheme_proc(int4) RETURNS
int4<br />    AS 'SELECT COUNT(i_theme) FROM tbl_theme <br />    WHERE i_theme = $1;' <br />    LANGUAGE 'sql'; <p>and
Icreated a trigger: <br /> CREATE TRIGGER chk_itheme_trig BEFORE INSERT OR UPDATE ON tbl_article <br />    FOR EACH ROW
EXECUTEPROCEDURE chk_itheme_proc ('theme'); <p>but I get the message: <br />     ERROR:  CreateTrigger: function
chk_itheme_proc()does not exist <p>If I do: <br />SELECT theme FROM tbl_article <br />   WHERE chk_itheme_proc(5) = 1; 
--i_theme goes from 1 to 12 <p>theme <br />----- <br />   11 <br />(1 row) <p>If I do now: <br />SELECT theme FROM
tbl_article<br />   WHERE chk_itheme_proc(15) = 1; <br />theme <br />----- <br />(0 row) <p>So I can see that the
functionis available .... <p>I'm stuck with this issue and I wasn't able to find any help on <br />documentations.
<p>Isthere somebody who could help me ??? <p>Many thanks in advance, <br />PhiL <pre>-- 
 
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