dogs_ball.sql

drop table if exists dogs, balls, dogs_balls;

create table dogs (
  id int not null,
  name varchar(255),
  primary key (id)
);

create table balls (
  id int not null,
  color varchar(255),
  primary key (id)
);

create table dogs_balls (
  dog_id int not null,
  ball_id int not null,
  primary key (dog_id, ball_id)
);

insert into dogs (id, name) values
  (1, 'Rex'),
  (2, 'Belka'),
  (3, 'Strelka'),
  (4, 'Snoop'),
  (5, 'Toto');

insert into balls (id, color) values
  (1, 'red'),
  (2, 'orange'),
  (3, 'yellow'),
  (4, 'green'),
  (5, 'blue');

insert into dogs_balls (dog_id, ball_id) values
  (1, 1), (1, 2), (1, 3),
  (2, 1), (2, 2), (2, 3), (2, 4),
  (3, 1), (3, 2), (3, 3), (3, 4), (3, 5),
  (4, 1), (4, 2),                 (4, 5),
                                  (5, 5);

-- Find dogs which have red, orange, yellow and green balls