Pierre,
you, probably, can use custom configuration, which uses pg_3chars
dictionary.
Oleg
On Mon, 30 Jun 2008, Pierre Thibaudeau wrote:
> 2008/6/30 Oleg Bartunov <oleg@sai.msu.su>:
>> tsearch will have prefix search support in 8.4.
>
> Thanks Oleg! That's fantastic news!
>
> In the meantime, carrying on with my earlier idea, here's the little
> function I came up with for extracting the 3-char-lexeme tsvector, in
> case anyone's interested:
>
> CREATE OR REPLACE FUNCTION public.to_three_char_tsvector(str text)
> RETURNS tsvector AS
> $BODY$declare
> somerow record;
> shortened_text text := '';
> BEGIN
> FOR somerow IN SELECT regexp_split_to_table(trim(both '\'' from
> strip(to_tsvector('simple',str))::text),'\'') AS item LOOP
> shortened_text := shortened_text || ' ' ||
> COALESCE(substring(somerow.item for 3), '');
> END LOOP;
> RETURN strip(to_tsvector(shortened_text));
> END;$BODY$
> LANGUAGE 'plpgsql' IMMUTABLE;
>
>
Regards,
Oleg
_____________________________________________________________
Oleg Bartunov, Research Scientist, Head of AstroNet (www.astronet.ru),
Sternberg Astronomical Institute, Moscow University, Russia
Internet: oleg@sai.msu.su, http://www.sai.msu.su/~megera/
phone: +007(495)939-16-83, +007(495)939-23-83