text: CREATE TABLE serials (
    id INT GENERATED ALWAYS AS IDENTITY PRIMARY KEY,
    title VARCHAR(30) NOT NULL,
    release_year INT NOT NULL
  );
  
  CREATE TABLE films (
    id INT GENERATED ALWAYS AS IDENTITY PRIMARY KEY,
    title VARCHAR(30) NOT NULL,
    release_year INT NOT NULL
  );
  
  CREATE TABLE top_rated_films (
    id INT GENERATED ALWAYS AS IDENTITY PRIMARY KEY,
    title VARCHAR(30) NOT NULL,
    release_year INT NOT NULL,
    rate INT NOT NULL
  );
  
  INSERT INTO serials (title, release_year) VALUES ('squid game', 2021), ('queen`s gambit', 2020);
  INSERT INTO films (title, release_year) VALUES ('spider-man: no way home', 2021), ('the gentelmen', 2020);
  INSERT INTO top_rated_films (title, release_year, rate) VALUES ('spider-man: no way home', 2021, 8);
  
  SELECT * FROM serials WHERE release_year = 2020
  --- don't remove dubles
  UNION ALL
  SELECT * FROM films WHERE release_year = 2020;
  
  SELECT title, 'top_rated_films' as source FROM top_rated_films WHERE release_year = 2021
  --- remove dubles
  UNION
  SELECT title, 'films' as source FROM films WHERE release_year = 2021;