trigger-function-on-update.sql

CREATE FUNCTION comment_text_search_trigger() RETURNS trigger AS $$
begin
  new.tsv_comment_text :=
    setweight(to_tsvector(coalesce(new.story_title,'')), 'A') ||
    setweight(to_tsvector(coalesce(new.comment_text,'')), 'B');
return new;
end
$$ LANGUAGE plpgsql;

/* Trigger on update */
CREATE TRIGGER tsvector_comment_text_update BEFORE INSERT OR UPDATE
ON comments FOR EACH ROW EXECUTE PROCEDURE comment_text_search_trigger();