text: CREATE SEQUENCE tournament_id_seq;
  CREATE SEQUENCE player_id_seq;
  CREATE SEQUENCE register_id_seq;
  CREATE SEQUENCE game_id_seq;
  
  CREATE TABLE public.tournament (
      ID_TOURNAMENT integer DEFAULT nextval('tournament_id_seq') PRIMARY KEY,
      NAME_TOURNAMENT varchar(250)  not null,
      DATE_INCLUSION date not null
  );
  
  CREATE TABLE public.player (
      ID_PLAYER integer DEFAULT nextval('tournament_id_seq') PRIMARY KEY,
      NAME_PLAYER varchar(100)  not null,
      DATE_INCLUSION date not null
  );
  
  CREATE TABLE public.register (
      ID_REGISTER integer DEFAULT nextval('register_id_seq') PRIMARY KEY,
      ID_PLAYER integer REFERENCES player (ID_PLAYER),
      ID_TOURNAMENT integer  REFERENCES tournament(ID_TOURNAMENT), 
      DATE_INCLUSION date not null
  
  );
  
  CREATE TABLE public.game (
  	ID_GAME integer DEFAULT nextval('game_id_seq') PRIMARY KEY,
  	ID_REGISTER integer REFERENCES register (ID_REGISTER),
      ID_TOURNAMENT integer REFERENCES tournament (ID_TOURNAMENT),
      ID_PLAYER1 integer REFERENCES player (ID_PLAYER),
      ID_PLAYER2 integer REFERENCES player (ID_PLAYER),
      MATCH_RESULT integer not null,
      DATE_INCLUSION date not null
  
  );