Message-ID: <20040224185806.51777.qmail@web13802.mail.yahoo.com>
Date: Tue, 24 Feb 2004 10:58:06 -0800 (PST)
From: Chris Gamache <cgg007@yahoo.com>
Reply-To: cgg007@yahoo.com
Subject: tsearch2 trigger alternative
To: pgsql-sql@postgresql.org
In-Reply-To: <200402241711.20947.dev@archonet.com>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii

Tsearch2 comes with its own tsearch2 trigger function. You pass column names to
it, and it puts a vanilla tsvector into the column names in TG_ARGV[0] (zero
based, yes?). Not only can you pass column names to it, but you can pass simple
functions to it as well. This is magical to me. :)

I'm trying to figure out how to do the same thing, except instead of returning
a vanilla tsvector, I want to return a specially weighted tsvector. I've
created a function that can do this:

create or replace function name_vector (text) returns tsvector as '
select setweight(to_tsvector(substr($1,1,strpos($1,'',''))),''C'') ||
to_tsvector(substr($1,strpos($1,'','')+1,length($1)));
' language 'sql';

so... 

Plain:

select to_tsvector('Einstein, Albert');
       to_tsvector
-------------------------
 'albert':2 'einstein':1

Weighted:

select name_vector('Einstein, Albert');
       name_vector
--------------------------
 'albert':2 'einstein':1C


Now, to somehow package that into a magical trigger function... 

All the examples for creating trigger functions that I've found use static
column names, NEW and OLD ... I would like to create a generic trigger
function, as the tsearch2 trigger function does, to return the specially
weighted tsvector.

Its like a lighter to a caveman. Can anyone lend a hand?

CG

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