dict_voikko
PostgreSQL full text search dictionary extension utilizing the Finnish dictionary Voikko.
dict_voikko uses the base form of Finnish words as lexems. For compound words it uses the base form of the non-compound words from which the compound word is built. If dict_voikko doesn't recognise the it returns NULL, so dict_voikko should always be chained with another dictionary.
Dependencies
The dictionary needs libvoikki and its dependencies. A suomi-malaga dictionary with morphological analysis for Voikko is neede (e.g. dict-morpho from http://www.puimula.org/htp/testing/voikko-snapshot/) and at the moment it needs to be called mor-morpho.
Installation
Put dict_voikko in [POSTGRES]/contrib/ and compile.
###In PostgreSQL
Run something like:
CREATE EXTENSION dict_voikko;
CREATE TEXT SEARCH DICTIONARY voikko_stopwords (
TEMPLATE = voikko_template, StopWords = finnish
);
CREATE TEXT SEARCH CONFIGURATION voikko (COPY = public.finnish);
ALTER TEXT SEARCH CONFIGURATION voikko
ALTER MAPPING FOR asciiword, asciihword, hword_asciipart, word, hword, hword_part
WITH voikko_stopwords, finnish_stem;
Test with
select ts_lexize('voikko', 'kerrostalollekohan');
The result should be:
ts_lexize
-----------
{kerros,talo}
(1 row)