text: SELECT 'A wise man always has something to say, whereas a fool always needs to say something'::tsvector;
  SELECT to_tsvector('english', 'A wise man always has something to say, whereas a fool always needs to say something');
  SHOW default_text_search_config;
  
  SELECT 'A wise man always has something to say, whereas a fool always needs to say something'::tsvector @@ 'wise'::tsquery;
  SELECT to_tsquery('english', 'wise & man'), plainto_tsquery('english', 'wise man');
  SELECT to_tsvector('A wise man always has something to say, whereas a fool always needs to say something') @@ to_tsquery('wise <-> man');
  
  SELECT 'elephants'::tsvector @@ 'elephant';
  SELECT to_tsvector('english', 'elephants') @@ to_tsquery('english', 'elephant');
  SELECT to_tsvector('simple', 'elephants') @@ to_tsquery('simple', 'elephant');
  SELECT setweight(to_tsvector('english', 'elephants'),'A') || setweight(to_tsvector('english', 'dolphin'),'B');
  
  SELECT ts_rank_cd (setweight(to_tsvector('english','elephants'),'A') || setweight(to_tsvector('english', 'dolphin'),'B'),'eleph' );
  SELECT ts_rank_cd (setweight(to_tsvector('english','elephants'),'A') || setweight(to_tsvector('english', 'dolphin'),'B'),'dolphin' );