pg_tsparser - parser for text search

Introduction

The pg_tsparser module is the modified default text search parser from PostgreSQL 9.6. The difference between tsparser and default parsers is that tsparser gives also unbroken words by underscore character.

License

This module available under the same license as PostgreSQL.

Installation

Typical installation procedure may look like this:

$ cd pg_tsparser
$ sudo make USE_PGXS=1 install
$ make USE_PGXS=1 installcheck
$ psql DB -c "CREATE EXTENSION pg_tsparser;"

After this you can create your own text search configuration:

CREATE TEXT SEARCH CONFIGURATION english_ts (
    PARSER = tsparser
);

COMMENT ON TEXT SEARCH CONFIGURATION english_ts IS 'text search configuration for english language';

ALTER TEXT SEARCH CONFIGURATION english_ts
    ADD MAPPING FOR email, file, float, host, hword_numpart, int,
    numhword, numword, sfloat, uint, url, url_path, version
    WITH simple;

ALTER TEXT SEARCH CONFIGURATION english_ts
    ADD MAPPING FOR asciiword, asciihword, hword_asciipart,
    word, hword, hword_part
    WITH english_stem;

Examples

Example of difference between tsparser and default:

SELECT to_tsvector('english_ts', 'pg_trgm');
         to_tsvector
-----------------------------
 'pg':2 'pg_trgm':1 'trgm':3
(1 row)

SELECT to_tsvector('english', 'pg_trgm');
   to_tsvector
-----------------
 'pg':1 'trgm':2
(1 row)