CREATE TABLE memos (
  id integer,
  content text
);

INSERT INTO memos VALUES (1, 'PostgreSQL is a RDBMS.');
INSERT INTO memos VALUES (2, 'Groonga is fast full text search engine.');
INSERT INTO memos VALUES (3, 'PGroonga is a PostgreSQL extension that uses Groonga.');

CREATE INDEX grnindex ON memos
  USING pgroonga (content pgroonga_text_regexp_ops_v2);

SET enable_seqscan = on;
SET enable_indexscan = off;
SET enable_bitmapscan = off;

SELECT id, content
  FROM memos
 WHERE content &~ 'groonga';

DROP TABLE memos;
